Weald Aquatics | Aquarium & Pond Fish Shop in Kent | The Weald Aquatics Blog - Aquarium maintenance


Coolings Green & Pleasant
Main Road, Knockholt, Kent TN14 7LJ

01959 532 963

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and Public Holidays: 09:00 - 16:00
Sunday: 10:00 - 16:00

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Water Testing in a Freshwater Aquarium

Blog post written by Gary | 16 February 2018 | Category: Aquarium maintenance

The main factor in successful fishkeeping and fish health lies in the maintenance of good quality water.

Aquarium water can be very deceptive. It can be crystal clear and yet be toxic to the fish or it can be cloudy and be safe for the fish. To check if your water is okay for the wellbeing of your fish you will need to test for the most common parameters which can affect the quality of the aquarium water.

Ammonia, nitrite, nitrate, pH, GH and KH are the 6 key parameters to test in the aquarium. Phosphate is another parameter to consider.

Test kits are available as test strips, liquid test kit, or tablet test kit. Test strips usually have 6 tests on one strip allowing you to look at nitrite, nitrate, pH, KH, GH and chlorine in one test with the results in about 30 seconds. Liquid and tablet test kits are individual tests which can take up to 10 minutes before a result of the water quality is known.

Liquid and tablet test kits are normally more accurate than the test strips and work out cheaper per test as you can get 60-80 tests from a test kit. The only problem with liquid and tablet test kits is that they take up a lot of room in the aquarium cabinet. Liquid and tablet test kits can also be purchased as a combined test kit containing the 6 key parameter tests which works out cheaper against buying the kits individually.

All test kits contain full instructions detailing optimum levels and suggestions for correction, along with test tubes, test tube racks and colour-coded stickers for conducting the same test in the same tube to avoid contamination.

Here at Weald Aquatics we also test customers’ aquarium water. If you are worried about your aquarium water please bring a sample in to us and we can check and advise on any problems shown up in the test.


Ember Tetras
Using a test strip to test different water parameters

Nitrate in freshwater aquariums

Blog post written by Gary | 08 February 2017 | Category: Aquarium maintenance

High levels of nitrate can build up in an aquarium over a period of time and not be noticed. This can cause problems with water quality and fish health. Algae growth will be more of a problem on the plants, glass and gravel, the fish will become stressed and more susceptible to bacterial and other disease related problems.

Nitrate accumulates in the aquarium water due to the nitrogen cycle which in its simplest terms breaks down fish and organic waste into nitrate. Some of the nitrate will be will be removed from the water by vigorous plant growth, however the majority of the nitrate in the aquarium will gradually build up to excessive levels.

The quickest and easiest way to keep nitrate at acceptable levels is to change between 15% and 25% of the aquarium water weekly. This amount is dependent on the type and quantity of fish being kept. Not overfeeding and keeping the gravel and filter system clean will also reduce the amount of nitrate accumulating in the aquarium water.

There are products which will help break down the nitrate in the aquarium such as Tetra Nitrate Minus and various sludge digesting weekly treatments including Bacterlife and API Stress Zyme. These products will reduce nitrate levels, however weekly water changes are the most effective at reducing nitrate levels.

Monitoring nitrate concentration is the most effective way to keep the aquarium water parameters at ideal levels. This can be achieved using either a dedicated liquid nitrate test kit or a multi test strip.

Keeping nitrate levels at 25mg/litre or lower will not only keep the fish in excellent condition but will also not cause any undue stress in newly introduced fish.

If you want to know more, just pop into the shop and ask any of the Weald team.


An explanation of the nitrogen cycle
An explanation of the nitrogen cycle

pH in the aquarium

Blog post written by Gary | 21 October 2016 | Category: Aquarium maintenance

The pH value of water in simple terms indicates whether water is acidic, alkali or neutral.

The pH scale starts from 0 which is the most acidic going up to 14 being the most alkali. A pH of 7 is neither acidic nor alkali and is considered neutral. The pH scale is logarithmic which means a small change in the pH value  actually equates to a large change to the water as each pH unit is a tenfold increase or decrease on the previous value.

Fish have evolved to live in water as low as pH5 to as high as pH9.5. However most freshwater fish live between pH6 and pH8.2. When keeping a mixed community of freshwater fish a pH of 7 to 7.2 is ideal. Both African Cichlids and marine fish have specific pH values for their aquarium setups.

Excessive high or low pH levels and fluctuations will cause stress in the aquarium, possibly leading to poor fish colour, poor appetite and a lowering of the resistance to disease. To keep the aquarium water at ideal pH levels, regular testing of the aquarium water is essential. It will indicate if the pH is gradually being lowered by the action of the fish waste being broken down into nitrates and carbon dioxide produced by the fish. Regular water changes will usually bring the aquarium water back to a pH of 7 to 7.2 (depending on the pH of the mains water).

To keep aquarium water at a specific pH value there are buffers available, which, as the name suggests, will keep the water at the specified pH level. Also available are additives which will raise the hardness of soft or RO water whilst keeping the pH at about pH7. 


Products for adjusting the pH of aquarium water
Products for adjusting the pH of aquarium water


Phosphates In The Aquarium

Blog post written by Gary | 26 August 2016 | Category: Aquarium maintenance

You will find both man-made and natural sources of phosphates in freshwater and marine aquariums.

These phosphates will feed problem algae which, in a freshwater aquarium will cover the gravel, ornaments and plants making the aquarium unsightly and also causing the plants to die back through lack of light on the leaves.

In marine aquariums nuisance algae can overrun and again cover the corals, potentially killing them. High phosphates in a marine reef aquarium will also cause problems for corals by affecting the formation of coral skeletons.

Phosphate levels in freshwater aquariums should ideally be below 0.04 mg/l and in marine aquariums should be at a lower level of 0.016 mg/l.

To achieve low phosphate levels in the aquarium water, regular water changes will help as this reduces phosphates from the food fed to the fish. However tap water also contains natural phosphates which are not removed by using a water conditioner.

The most effective way to remove phosphates from the aquarium water is by using a granular phosphate remover such as Rowaphos or API Prevent Algae. These are placed in the aquarium filter and removed when exhausted. The length of time the phosphate removal media is in the filter will depend on the level of phosphate saturation in the aquarium.

For more information regarding Rowaphos why not come in and chat to us.


Rowaphos and API Prevent Algae
Rowaphos and API Prevent Algae - two tools in your armoury against phosphates

Why Is My Aquarium Water Cloudy?

Blog post written by Gary | 26 August 2016 | Category: Aquarium maintenance

Cloudy water normally affects new aquarium setups; however it can also become a problem in an established aquarium.

There are usually two causes of cloudy water in the aquarium:


Fine particles floating in the water not being removed by the filter system.

To clear the cloudy aquarium, a number of 30% water changes can be carried out. Alternatively use an aquarium treatment such as Tetra CrystalWater which binds the small particles into larger particles making the filter more effective. The aquarium will normally become crystal clear in 12 hours.

To avoid a cloudy aquarium when either setting up a new aquarium or replacing the gravel, make sure the gravel is thoroughly washed using cold tap water.


Lack of beneficial bacteria in the filter system.

This milky cloudiness can again be cleared by a number of 30% water changes and also adding into the aquarium beneficial bacteria such as Bacterlife or Stress Zyme. The milky cloudiness can take a couple of days to disappear.

By not adding too many fish too quickly to a newly set up aquarium and not washing all the filter media in tap water you can avoid a milky cloudy aquarium.


A range of treatments you can use to get rid of cloudy water
A range of treatments you can use to get rid of cloudy water

Whitespot in Freshwater Aquariums

Blog post written by Gary | 25 May 2016 | Category: Aquarium maintenance

Whitespot is one of the most common and highly contagious diseases found in freshwater aquariums and without treatment can cause a loss of fish.

Having an outbreak of Whitespot in the aquarium can be caused by a water temperature difference when changing aquarium water, water quality when introducing new fish and possibly introducing too many fish too quickly into an aquarium.

Whitespot disease is easy to identify as the fish will have very small (sugar grain size) whitespots over the body. Other symptoms include fish gasping at the water surface and a change in the fish behaviour. If left untreated the infection will spread to other fish in the aquarium and the fish already infected will be become re-infected leading to more white spots on the fish.

Whitespot disease is caused by a microscopic parasite which will leave an infected fish to multiply and find other fish to infect. To effectively eradicate the disease from the aquarium the parasite has to be killed in its free swimming state.

As soon as Whitespot is detected it is best to treat the aquarium to stop the disease spreading. The best treatment we find is Waterlife Protozin which when used as directed will usually clear a Whitespot problem in one application. As with any treatment in the aquarium, all carbon or chemical removing media will need to be removed from the filter during the treatment.

During the Whitespot infection the fish may be prone to a secondary fungus or bacterial infection which will also need to be treated. Fish that have survived an attack of Whitespot will be less susceptible to another outbreak.

Some fish, particularly clown loach seem to be more susceptible to Whitespot. These fish will normally give you the first indications if there is a problem in the aquarium. 



Getting rid of pollutants in aquarium water

Blog post written by Gary | 28 April 2016 | Category: Aquarium maintenance

Over the years we occasionally have customers coming into the shop asking why their fish are dying unexpectedly. Most cases can be explained but some cases take longer to solve.

Many of the problems with the unexplained fish deaths can be due to airborne pollutants such as air fresheners, fly sprays, spray polish, carpet sprays and, if the aquarium is in a bedroom, deodorant and perfume sprays. Leaving soap on your hands or not adequately rinsing your hands before dipping into the aquarium can also cause the same problems.

If the cause of the unexplained fish deaths is due to a pollutant, the easiest solution is to dilute the chemical in the aquarium water by doing a number of water changes of at least 30% (never more than 50% of the aquarium volume in one water change). This will help the fish in the aquarium.

To quickly remove all the chemical pollutants, use a Poly-Filter. This pad is a unique invention for chemical filtering and purifying both freshwater and seawater. The pad will fit any filter system and changes colour when indicating what pollutants it has removed and when it needs to be changed.  The Poly-Filter will not release the impurities back into the aquarium.

One standard Poly-Filter will treat up to 180 litres at a price of £15.49.



Why Use Carbon in Aquariums?

Blog post written by Gary | 22 March 2016 | Category: Aquarium maintenance

Activated carbon is one of the cheapest, most effective and easiest ways of removing organic pollutants, odours and water discolouration from the aquarium. Aquariums laden with a high organic waste can often experience reduced fish growth and are more susceptible to fish disease. By reducing the organic and toxic compounds in the aquarium water, the water quality improves leading to healthier fish.

Carbon removes organic pollutants from the aquarium water by adsorption, which means the organic compounds are removed from the aquarium water by attaching themselves to the outside of the carbon and then held there by electrostatic force.  As carbon adsorbs toxic substances from the aquarium it has a limited working life of about 3 to 4 weeks before it will need to be changed. As most carbon is sold by volume, a general guide of 500ml will treat approximately 50 gallons/225 litres.

In some filter systems the carbon is impregnated into a filter sponge for ease of use. This system will still remove toxic compounds from the aquarium and will still need to be changed according to the manufacturer's instructions.

If you are treating your aquarium with medication, all carbon filtration will need to be removed from the filter as it will remove the treatments, making them ineffective. When the course of treatments has been completed, the carbon can be placed back into the filter.


Activated carbon
Carbon filter sponges

Quick and easy water testing

Blog post written by Gary | 17 February 2016 | Category: Aquarium maintenance

Your fish and plants will thrive and grow if the water in the aquarium is kept at its optimum quality. Over time, it is very easy for the Nitrate and pH to reach toxic levels even if you are changing the water regularly.

To monitor your aquarium water it is ideally best to check the quality once a month, as this time span will pick up any problems that could potentially be building up in your aquarium water. This then allows you to effectively deal with the problem before the fish are affected by the water quality.

Using a test strip allows you to check up to 6 parameters in one go, giving a quick visual guide to any problems which may be present in the aquarium water. Most test strips have Nitrate, Nitrite and pH as the main essential tests, with secondary tests being GH, KH and Chlorine.

All test strips are easy to read with colour graduation results showing when a water parameter is incorrect and how to rectify to bring the water back to optimum quality.

At Weald Aquatics we have Tetra 6 in 1 and API 5 in 1 test strips. Both have 25 test strips which will give you up to two years of water testing. Tetra 6 in 1 test strips are for freshwater testing only; API 5 in 1 test strips can be used for testing both freshwater and saltwater aquariums.

Tetra 6 in 1 test strips include Nitrate, Nitrite, pH, KH, GH, and Chlorine. Price £12.75

API 5 in 1 test strips include Nitrate, Nitrite, pH, KH and GH. Price £11.99


Test strips
API and Tetra test strips


Why do we use a water conditioner?

Blog post written by Gary | 15 January 2016 | Category: Aquarium maintenance

Mains tap water is treated with chlorine or chloramines which are disinfectants, both being toxic to aquatic life. Also found in tap water are the heavy metals: copper, zinc and lead. Again these are very toxic to all aquatic inhabitants.

The effect that toxic chemicals have on fish in the aquarium is that chlorine destroys the gill tissue causing suffocation, and chloramines which pass through the gills and then enter the bloodstream, lead the iron in the blood cells to bind, preventing them from carrying oxygen essentially suffocating the fish.

By treating your tap water with a quality water conditioner it will prevent the toxic chemicals from harming your fish. All of our water conditioners work by instantly neutralising both the chlorine and chloramines and completely binding the heavy metals present in tap water.

Water conditioners also add essential elements including iodine and magnesium to the water along with added vitamins to keep your fish healthy. Gill and mucous membranes on the fish are also protected along with added bio colloids for beneficial bacteria growth. 


Water conditioners
Various water conditioners

When to change the filter media in a Juwel aquarium

Blog post written by Gary | 04 September 2014 | Category: Aquarium maintenance

To help our customers with Juwel aquariums keep their filter systems in good working order, we have with the assistance of Juwel assembled a timetable to show when filters should be changed and a list of the new names for the Juwel filter media.

Juwel media name change

Previous Name     New Name
Poly Pad    bioPad
Carbon Sponge  bioCarb
Nitrax Nitrax
Filter Sponge Coarse  bioPlus coarse
Filter Sponge Fine  bioPlus fine
Cirax Cirax
Phorax Phorax

Juwel filter change timetable

bioPad    Weekly
bioCarb    Monthly
Nitrax Two Months
bioPlus Coarse   Three Months
bioPlus Fine    Nine Months
*Cirax   Twelve Months
*Phorax    Two Weeks
*Carbax    Two Months

*If you have the optional filter media fitted.

For the positioning of the filter media please see the drawing below. You can also download this image as a PDF file for easier legibility by clicking here. The above timetable is for all aquariums in the Juwel range.


Juwel factsheet

Update on our maintenance service

Blog post written by Gary | 30 May 2014 | Category: Aquarium maintenance

It is now over a year since we began our aquarium and pond maintenance service and in that time we have serviced and built over 400 ponds and aquariums.

As the number of regular maintenance customers has increased we have had to invest in a new van. The van is now a regular sight on the roads around Bromley, West Wickham, Orpington and Sevenoaks and we are also maintaining a number of aquariums in the Bexleyheath and Dartford area.

As mentioned earlier we service both freshwater and marine aquariums and ponds. For aquariums the cost will depend on the size of the aquarium and whether it is a marine aquarium or a freshwater aquarium.

For a service on both types of aquarium a water test is taken, the filters, gravel, ornaments and glass are cleaned, a partial water change carried out and then the aquarium is aquascaped. With marine aquariums further water tests and equipment cleaning are undertaken.

With ponds we have three levels of pond service: a full service, half service and mini service. The pond services are comprehensive and too long to list here so please contact us for more detailed information regarding the work carried out on each service.


You won't miss our van as it travels about the locailty. We've got tropical fish on one side...
You won't miss our van as it travels about the locality. We've got tropical fish on one side...


...and marine on the other.
...and marine on the other.

RO water and RO salt water

Blog post written by Gary | 03 February 2014 | Category: Aquarium maintenance

Water from domestic taps is not really the best water to use in aquariums especially marine aquariums as it contains chlorine, phosphates, nitrate  and heavy metals (lead, copper and many more) which are not ideal for fish keeping. For most coldwater and tropical freshwater fish, using a water conditioner is adequate for making the water safe for the fish.  Discus and marine fish however require water of a higher standard to keep them happy.

To achieve the best results for your fish and invertebrates and also minimise nuisance algae, RO water should be used for both top-ups and water changes in both marine and freshwater aquariums.

RO is short for reverse osmosis which as the name implies, is the opposite of natural osmosis. To purify tap water, water is forced under pressure through a semi-permeable membrane which filters out minerals, contaminants and impurities making the water ideal for marine aquariums and also for drinking.

As RO water is pure water it has an unstable pH due to all the minerals being removed. If being used in freshwater aquariums, a mineral additive such as Tropic Marin Re-Mineral Tropic should be added to the RO water to stabilise the pH and to and achieve the correct hardness of water required for the aquarium.

RO systems are available for home plumbing, but if you find this too much hassle we have both RO water and salted RO water in 25 litre and 10 litre containers available in the shop. For more information please talk to one of the Weald team.

Ammonia and Nitrite in freshwater aquariums

Blog post written by Andy | 04 June 2013 | Category: Aquarium maintenance

Last month in our blog we wrote about nitrates in aquarium water. In this blog we will look at ammonia and nitrite which are eventually broken down into nitrates.

Ammonia is excreted by fish which is immediately broken down into nitrite in a matured aquarium by the bacteria in the filter system. The nitrite is then broken down into nitrates by different bacteria in the filter system.

Both ammonia and nitrite are toxic to fish even in small concentrations, so it is to best avoid having both in the aquarium.

When starting a new aquarium, levels of bacteria in the filter system will be zero and therefore unable to break down both ammonia and nitrite. In order to keep both these levels as low as possible, new fish should be added slowly along with treatments to boost the filter bacteria such as Bacterlife or API Stress Zyme.

With a matured filter system, both ammonia and nitrite will be kept at acceptable levels. However these levels will rise if the bacteria in the filter are killed by either washing all the filter media in tap water or the filter system pump stops working for a number of hours.

In the event of losing all the bacteria in the filter system, you will need to change at least 30% of the water and add a double dose of either Bacterlife or API Stress Zyme every two days for about a week until the bacteria returns to the correct levels. Also feeding the fish every two days will to help the bacteria levels return to normal concentrations.

Monitoring ammonia and nitrite concentrations is the most effective way to check that the aquarium water parameters are at ideal levels. This can be achieved using dedicated liquid ammonia and nitrite test kits. Keeping ammonia levels at 0.3mg/litre or lower and nitrite levels lower than 1mg/l will not only keep the fish in excellent condition but will also not cause any undue stress in newly introduced fish.


API Stress Zyme
Bacterlife and API Stress Zyme will help to keep bacteria at the correct levels in your filter.

Interpet PF1, PF2, PF3 and PF4 filter cleaning

Blog post written by Gary | 04 April 2013 | Category: Aquarium maintenance

Our pictorial guide below takes you through the whole process of cleaning the Interpet PF1, PF2, PF3 and PF4 filters. We hope you find it useful.


Having removed the filter from the aquarium, push finger indents on either side of the filter body whilst pulling the pump head at the same time, this will separate the filter from the pump head.



Once the head is removed pull the foam carrier out to clean the foams and tip away any water in the body of the filter. Foams should be washed in a bucket of water containing aquarium water. The carbon foam should be replaced every 3 to 6 weeks. Both the foam and carbon foam should not be washed under tap water as this will destroy the beneficial bacteria.


The Bio chamber should be cleaned every 6 months. To do this grasp the bio chamber firmly and twist and pull the container from the filter head.  As with the sponges the biomedia should only be cleaned in aquarium water.


To gain access to the impellor, pull the cover away from the head unit.


Pull the impellor away from the head unit and use a soft brush to clean the impellor and impellor chamber.



To clean the aqua valve, unclip the cover from the filter body this gives you access to the aqua valve for cleaning. This should be carried out every 6 to 8 weeks. Filter should be assembled in reverse order.

Superfish Aquaflow 100/200 filter cleaning

Blog post written by Gary | 09 March 2013 | Category: Aquarium maintenance

Our pictorial guide below takes you through the whole process of cleaning the Superfish Aquaflow aquarium filters. We hope you find it useful.


With the filter removed from the aquarium, hold the pump head and push on either side of the filter cartridge and pull away from pump head in the direction of the arrow on the cartridge.


To clean the sponge, unclip the bottom of the cartridge and remove the sponge. The sponge should only be cleaned in water taken from the aquarium. Superfish recommend the filter cartridge be replaced every month.


To gain access to the impellor, remove the bottom plate from the pump head.


Carefully remove the impellor assembly and clean with a soft brush also clean the impellor chamber. The impellor should be cleaned every 3 to 6 months. Filter should be assembled in reverse order.

Bacterial Problems in Aquariums

Blog post written by Gary | 09 March 2013 | Category: Aquarium maintenance

Bacteria can affect fish in a number of different ways in both external and internal infections. To minimise the risk of bacterial infections with existing fish, good water quality is essential. This can be achieved by regular water changes and keeping the gravel and filters clean.  Regular water changes will also help to keep algae problems to a minimum.

Internal bacteria can cause dropsy, where the fish develops a bloated appearance with scales sticking out from the fish; also fish can lose buoyancy and float upside down. Many unexplained deaths can also be due to internal bacterial problems.

With external bacterial infections, fin and tail rot and ulcers are the most common problems. The signs of fin and tail rot are ragged and split fins which, if not treated quickly, can erode both the fin and tail completely. Ulcers appear as open red sores on the body and again, if not treated quickly, can spread on the fish and to other fish in the aquarium.

External bacterial problems which are not so common are cloudy/pop eye and mouth fungus. A fish with the cloudy eye or pop eye will develop a whitish haze over the eye and/or the eye may protrude from the head.

Mouth fungus is not actually a fungal infection but caused by a common bacterium. The symptom of mouth fungus is usually white cottony tufts around the mouth, skin and fins of the fish.

There are many treatments available for bacterial infections. The two treatments we have found the most effective are the API Melafix and Pimafix for external bacterial problems, and Interpet No. 9 Anti Internal Bacteria for all internal bacteria infections.


A range of products are available for treating bacterial and fungal infections.
A range of products are available for treating bacterial and fungal infections.

It's important to keep your gravel clean

Blog post written by Andy | 06 December 2012 | Category: Aquarium maintenance

Cleaning the substrate is one of the most important parts when maintaining a healthy aquarium.

Gravel not only provides a natural habitat for your fish, a rooting substrate for plants, makes a tank more aesthetically pleasing, but also provides an extra layer of biological and mechanical filtration in your fish tank.

Not only does the gravel catch waste, but beneficial bacteria colonise the gravel and break down fish waste and harmful biological products into less toxic substances. However this waste can only be broken down so far and if left in the aquarium can rot causing the build up of harmful elements. This can lead to water quality problems, fish health issues and algae blooms.

Gravel generally needs a decent clean once a month, but I would also recommend before your weekly water change, just to turn the gravel with your fingers. This allows you to syphon out any dirt particles that float up and also helps prevent algae growing over the top of your gravel.

We stock a great selection of air-driven, battery-operated, gravity-fed and mains-powered gravel cleaners for the smallest up to the largest fish tanks. Some will allow you to do a water change at the same time as cleaning your gravel whilst others recycle water allowing you to use them for longer periods of time.

Gravel cleaning should always be part of your general maintenance and once you're into a routine, should take you no time at all and benefit your fish and plants greatly.


Gravel cleaners
We stock a range of gravel cleaners - mains-operated, battery-operated and syphon action

Setting up a Marine Tank

Blog post written by Jon | 07 November 2012 | Category: Aquarium maintenance

Due to Andy's paternity leave (big Congrats to Andy & Amy!) I have been asked to fill in for this month's blog. I have recently set up a marine aquarium and it seems that lately more and more customers have been asking us about how to set them up - the costs, the maintenance and whether we will be stocking marine fish. I will focus this blog around these questions.

Now to get the easy bit out of the way - yes we will be stocking marine fish and the current plan is that in the new year we will change around the shop a bit (you're probably asking "again?!" but it's only a small change around!) - the pond fish will go outside and will give us the room for two marine banks.

Now then, how to set up a marine tank...

The equipment needed:


Prices vary with size - anywhere from £70 to £1000

We recommend the bigger the better, however, that is not to say small reefs don't work - all you have to do is search for Nano Reef and you'll see that many people have small reef tanks. My set up is 220 litres which is more than enough (I would suggest 100 litres minimum).


Prices vary with size - £64.99 to £169 for an external at the minimum size

Again the bigger the better. With marine fish the water quality is vital. Most of our customers tend to do a 20% water change weekly if they keep corals and 25% fortnightly if it is just fish. The filter is the most important part of the fish tank in my opinion, since it is the one bit of equipment which will look after the fish for you and maintain the water quality it is definitely worth investing in a good one (on our Facebook page I recently reviewed the Superfish Aqua-Pro range which is my personal favourite).


£20 to £35

1W of power for every litre of water in the tank.

Protein Skimmer

£65.99 (Nano) to £199 (for a 500 litre tank)

A protein skimmer is the only bit of equipment that is not needed in a tropical/coldwater tank. Its job in a marine tank is to take out organic proteins by turning them into foam before they break down into nitrogenous waste. The reason a protein skimmer is required is that most marine fish are sensitive to nitrates so extra precautions are needed.


£30 to £200 (entire light unit)

For a fish only marine tank you just need marine bulbs that you can get to fit into the majority of fish tank light units (Juwel, Arcadia etc.). If you want to keep Corals then it is advised to get high intensity lighting so T5 lighting should be the minimum.



A hydrometers will show you how much salt is in the water and the specific gravity of the water. They are simple to use and all you need to do is fill it with water make sure you have a specific gravity of around 1.021 to 1.024.

R.O. Water (reverse-osmosis)

£3 per 25 litres

In order to keep marine fish, ordinary tap water is not really suitable, it is best to use R.O. water which is water in a very pure form.


£14.99 to £45.59 depending on size

In the shop we sell Tropic Marin Pro Reef salt as we find it has all the essential elements needed to keep marine fish and corals.

Coral Sand

£4.99 for 5kg

This is a substrate that will be found naturally under the sea or around certain tropical beaches. It helps buffer the water to the right pH level and also is highly porous for filtering bacteria to live in.


Other recommended equipment:

  • Power heads to replicate the flow of the ocean. Through our experience any corals in a tank with a power head really do thrive.
  • Test kits

The most difficult aspect of setting up the marine tank was the learning curve at the beginning. However, after a few months you learn all the basics and it starts to become second nature. As long as you do your research and keep up regularly scheduled maintenance of the tank then it isn't as hard as people say. I spend about an hour a week maintaining my tank, which includes: doing a water change, wiping off algae, checking fish health, changing any filter media and feeding the fish.

In my tank I currently have - Blue-Hermit crabs, Clown Fish (Nemos!), Yellow-tailed Damsels (A fantastic shoaling fish - think Neon Tetras of the ocean), Green Coral Gobies and a Vagabond Butterfly. All the fish are from the supplier we get our tropical fish from (if you want any marine fish we can do a special order).


Jon's marine tank


There is a video of my aquarium on the Weald Aquatics Facebook page at http://www.facebook.com/photo.php?v=10151077181267676.

If you have any questions Andy and I run the Facebook page so just send us a message on there or pop in to the store and we'll be more than happy to answer your questions!

How to clean a Juwel filter

Blog post written by Andy | 01 August 2012 | Category: Aquarium maintenance

In the feedback our customers have given us from our monthly club email, one of the things we have been asked to do is to provide more hands-on information and articles about how to do things relating to your pond or aquarium. So this is the first of what we hope will become a regular feature of our blog.


1. Here we have our aquarium ready to be cleaned. The first step is to unplug the lighting, heater and filter pump.
2. Carefully remove the hood, being careful not to spill any water on any electrical plugs or sockets.


3. In the Juwel range of aquariums, all of the filter equipment is located in the black box in the corner.
4. Remove the top of the filter cover to gain access to the pump and media sections.


5. All of the filter media is kept in plastic sleeves to allow you easy access to whichever section needs cleaning.
6. Grasping the plastic handles on the sleeve, gently slide the sleeve upwards lifting the filter media with it.


7. Remove the appropriate sponge that needs cleaning / replacing. We are going to clean the top white polishing pad.
8. Clean / replace the sponge if necessary. As we are cleaning the top polishing filter we can clean it under tap water. Different sponges and media need replacing and cleaning differently depending on their function. If you need more information or you're just not sure, give us a call or come visit us in the shop.


9. Replace the cleaned or new filter sponge back into its correct place in the filter basket and slide back down into place.
10. To remove the pump you must first remove the outlet / flow director.


11. The pump again has two small handles to grip to allow easy removal.
12. Pulling gently upwards, remove the pump from the filter housing.


13. The pump itself comes apart to allow access to clean the impellor. Gently slide the base of the pump off. This can sometimes be tight, especially if you have never done it before.
14. Inside the centre of the pump you will see the impellor which sits on a metal spindle.


15. Gently remove the impellor.
16. Clean the magnet section with a fine brush to remove any dirt and clean the impellor blades in the same way.


17. Wash the other section of the pump and clean the metal spindle with the brush and clean tap water.
18. Reassemble the pump and place back into the filter box. Reattach the outlet pipe and filter cover. Plug your equipment back in and replace the hood. We use Juwel cleaning brushes to clean all our filters. They are available to purchase in store.


19. For the older style pump fittings, the socket is twisted 180 degrees anti-clockwise.
20. The socket can then be pulled away from the pump housing.


21. Slide the base of the pump off, this then reveals the impellor.
22. Gently remove the impellor for cleaning.


23. Re-assemble the pump in reverse.
24. The new Juwel Ecco pumps have the same socket as the Juwel Bioflow pumps.


25. To gain access to the impellor, the socket is twisted 45 degrees anti-clockwise and then pulled away from the pump housing.
26. The impellor including the shaft and rubber bush can be removed for cleaning.


I hope you found that useful and we'll be providing more of this sort of thing in future blogs.

See you all soon.