If you decide to keep fish, you will need to start thinking about their welfare, before they arrive. After all, you don’t want to buy them to watch them float belly up at the top of your tank, do you?
Prevention is always better than cure. Inevitably fish will get ill and eventually die which is unavoidable, but the aim of this article is to ensure that your new pets stay with you happily and healthily for as long as possible. Especially, as it can become very costly to keep having to replace them.
To set up and maintain a healthy tank, there are a few things you need to do BEFORE you buy your fish.
Size of Tank
Before you get any fish you need to think about, what type of fish you want to get and how many. This will determine the size of tank you need.
To keep your maintenance down to a minimum, it is best not to over stock your tank. As a general rule of thumb, you should have a gallon of water or 3.5 litres for every inch of fish in your tank. In other words, in a 12 litre tank you should not keep more than 4 fish which are each an inch long or 2 fishes which are each 2 inches long. You also need to do your homework on the fish you are planning to keep, as your tank needs to cater for the growth of the fish too. In other words, if you buy a baby fish which is an inch long in the pet shop, and it becomes 3 inches long as an adult fish, it could outgrow your tank.
Some very small fish, such as the mountain cloud minnows, look ideally small enough to keep in a small tank, but when you realise you need to keep 5 – 6 of them together, as they are shoaling fish, this means you will need to increase the size of your tank to cater for this too.
Therefore, the larger the tank, the more fish you can keep, but it will also be easier to maintain and clean. Ideally, a beginner’s tank should not be smaller than 40 litres or be less than 10 gallons in capacity, or no smaller than 2ft long, unless of course you are planning to keep a betta fish or a cherry shrimp tank.
Choosing your substrate and ornaments
The first thing you need to do is fill your tank with a substrate. This could be sand, pebbles, gravel or even soil to mimic the bottom of a river bed. If you are a beginner, avoid soil, as there are plenty of live plants you can use in your tank which do not need to be planted.
If you prefer to use artificial plants, do not use hard plastic plants. The general rule is – if they can snag ladies’ tights, then they can accidentally hurt your fish and should not be used. Silk plants are a much safer alternative to plastic plants.
Remember: Fish can also get cuts and grazes from sharp ornaments, sharp gravel and even rocks in your tank, which can lead to illnesses and deaths if infections set in. So choose these carefully.
If you use sand or gravel as a substrate, make sure you wash it thoroughly in clean running water before you put it into your tank. Rinse it, until all the sediment has been removed, otherwise your tank water will become very cloudy when the water is added and this could take weeks to settle, not forgetting could damage your filter.
Choose children’s play sand, as a cheap option, but check that it contains no additives which could be harmful to your fish. This is also a safer and softer alternative to builder’s sand. Special aquarium sand is best, but this tends to be much more expensive. Alternatively, choose gravel which is smooth and rounded without rough edges. As your fish could hurt their mouths, as they dig around the bottom. Be aware some coloured gravels can release pigment into the water which may not be safe for fish.
If you use rocks and stones from the garden, wash these thoroughly, then boil them in a pan of water for at least half an hour, to remove any bacteria that could harm your fish.
If you want to add natural bogwood or driftwood to your tank, then boil this first too in a pan of water, to leech out the tanins. Otherwise your tank water could turn a ‘tea’ brown colour, which is harmless to fish, but some people do not like the look of. Natural woods may also start to grow fungus in your tank, even after boiling, as the fungus feeds off the nutrients still left in the natural wood. This can be very unsightly, although harmless to fish. If you do not want fungus growing in your tank it is best to stick your natural wood in a bucket of water for a few weeks until the fungal cycle is over. After which, the fungus won’t come back. Then you can put it back into your tank safely. Alternatively, buy plastic ornaments which look like wood to decorate your tank.
Dechlorinate your water
Raw tap water contains chlorine so that it is safe for us to drink. Unfortunately this makes it poisonous for fish too. Therefore you should never put fish into raw tap water. Tap water first needs to be conditioned with a de-chlorinator to remove the chlorine before you stick fish in it. To do this, you will need to buy a liquid or powder water conditioner. Follow the instructions on how much to add to your water to make it safe for your fish. Usually, only a couple of ml (depending on the brand you use) needs to be used to make your tap water safe. Some de-chlorinators or water conditioners also contain good bacteria that can be added to your tank water to support the de-nitrifying process, and some even remove ammonia and nitrites, so choose the one that best suit your needs.
Live Plants
Some fish need live plants to hide in and even sleep in. They are also more natural than plastic plants. However, if you are a beginner, keeping plants too can be very daunting. Therefore choose plants that are easy to keep – for more information about easy to keep plants read: Live Aquarium Plants for Beginners
Use a filter
You need to use a good filter for your tank that is appropriate for the size of the tank you have.
The filter draws in the dirty water from your tank, keeps hold of all the bad stuff which gets trapped in the sponge and lets out the cleaner water from the outlet pipe.
The ‘good’ bacteria which lives and breeds within the sponge of your filter, breaks down everything poisonous, to keep your fish safe and healthy.
A filter with an adjustable water flow is best, so that the water outlet is not too strong. While some fishes like zebra danios do not mind strong currents in the water, betta fish prefer a more gentle flow. The filter is essential for cleaning out any uneaten food, fish poop and dead decaying matter, that could add to the ammonia load.
Not having a filter means all the decaying matter would simply rot at the bottom of your tank poisoning your fish.
Cycle your tank
Once you have arranged the things you want in your tank, and added your conditioned water, you then need to build up the ‘good bacteria’ in your aquarium. This is done through the process of ‘cycling’ your tank, before you buy any fish. This simply means setting up your tank as you want it to be, with gravel, ornaments, plants etc. filling it with conditioned water, running a filter, putting on the heater to the desired temperature (if you are going to use one), then running it as normal for a couple of weeks, but without any fish.
The aim of running a fish-less cycle (without getting too scientific), is to allow the good nitrifying bacteria to start building up in your filter sponge. This will help to break down the nasties your fish are going to produce once they are introduced.
But what nasties are fish going to produce? I hear you ask.
The reality is, out in the wild, fish swim freely in rivers and lakes and flowing water and have access to good bacteria, food and necessities naturally – all thanks to Mother Nature. A little like us walking around and breathing air freely. But as soon as we take them out of their natural habitat and stick them in an aquarium with other fish, Mother Nature can’t do her job, so we have to do it for her. In the same way, if we were stuck in a lift with other people for weeks on end, with no food, ventilation or anyone to remove the waste we produced, we’d get sick too. Ewww, I know. But now you get the picture.
One of the most poisonous gases fish breathe out is ammonia, and this needs to be constantly removed from the tank water. The easiest way to do this is to have ‘good’ bacteria in your tank that can break down the ammonia to nitrites. Unfortunately, nitrites are more poisonous than ammonia, so putting fish at an even greater risk of being poisoned. These nitrites, then need to be broken down further by other ‘good’ bacteria to less harmful nitrates. These nitrates can then be removed from the tank in two ways: by plants using them for their food or you removing them in your water changes.
Ammonia also builds up in the tank, when fish poop, fish die and plants die and decay too. Also if you over feed your fish and the left over food sits in the bottom of your tank and rots.
Therefore, if you put too many fish into your tank together and there are not enough bacteria in the filter to remove all the ammonia being produced, then your fish will become poisoned. This will cause them to become very ill and quickly die.
Therefore, the tank needs to be run for a few weeks, with the filter drawing the water through the sponge, to build up the bacteria; ready to break down any waste that passes through it. The more bacteria you have in the sponge, the safer the water will be when the fish are eventually added.
To speed up the cycling process, you can add a couple of hardy fish, such as zebra danios or white cloud mountain minnows to your tank. But they will be very uncomfortable, as the high toxin levels fluctuate in the tank during this process. The total cycling process can last up to a couple of months.
You can then start adding a few fish at a time, to allow the bacteria to multiply further, and meet the demands of the fish gradually.
Every time, new fish are added to the tank, this causes an ammonia spike, meaning the toxin levels increase rapidly, and can only be brought down by water changes or the bacteria multiplying in the filter.
To check that the ammonia and nitrite levels are low enough for new fish to be introduced, you should use a water testing kit to test the quality of the water, and levels of ammonia and nitrite too.
Prolonged exposure to ammonia or nitrites will lead to bacterial infections, fungal infections and illnesses in your fish, such as septicemia. This can be seen as blood streaks on the outside of a fish’s body, leading to mould or fungus growing on the fish’s body.
This can be very distressing for a pet owner to witness, as well as for the fish themselves, so good maintenance should be in place from the very start to ensure these problems do not occur.
Adding fish to your tank
Once your water test readings show that your tank is safe to add fish, add only a few fish to start with, so that the filter bacteria can cope with the ammonia spike.
Do not pour your fish into your tank with the shop water.
Newly bought fish can bring with them diseases and illnesses.
As they will already be stressed, after being chased around the pet shop tank to get them into your bag, they will be more susceptible to getting sick very quickly.
Do not add to their stress by pouring them into anything, as the speed can create shock and possibly death.
The water they come in from the pet shop could also be carrying horrible fishy diseases, so you do not want to pour these into your tank either.
So how do you introduce fish into your tank? Well there are two ways:
a. First of all, you can float the plastic bag with the fish in it, in your tank for 1/2 hour, to acclimatise the temperature in the bag to the temperature of your tank. This is to ensure that the fish do not dive into a hot or cold ‘bath’ causing them additional stress. The water inside the bag needs to match the temperature inside your tank, before they are introduced.
Once the fish have been acclimatised to your tank temperature, use a clean fish net to gently removed the fish from the bag and place them individually into the tank. Then throw away the water the fish came in.
b. If you already have some happy, healthy fish in your tank and you do not want your new fish to bring illnesses and diseases to them, do the following instead:
- Remove some of your tank water into another container, as you would do in a water change, then place your plastic bag in this water to acclimatise your new fish.
- As they are acclimatising – use a pipette and add a drop of methylene blue to the water in the plastic bag, to kill off any bugs or germs that the new fish maybe carrying.
After 20 – 30 mins, use a fish net to remove the fish from the methylene blue, and place them in the container their bag was floating in. Then throw the water from the bag away. After 5 -10 minutes, use the net again to take the fish from the container and place them into your aquarium. The purpose of placing them into a different container first, is to wash off an residual methylene blue from their body, before they enter your tank.
You do not want to get methylene blue in your tank water, as this could kill the ‘good’ bacteria in your filter. Then top your tank up with fresh conditioned water.
Test your water again regularly, to ensure your ammonia and nitrite results remain around 0.
If your readings start to rise above 0, do regular 10-20% water changes, every day or every other day, until the bacteria in the filter can keep the ammonia or nitrate levels down themselves.
Water changes
As well as building up your ‘good’ bacteria levels and using a good filter, you should also do regular water changes. This means, removing part of the polluted water from the tank every week and replacing it with fresh de-chlorinated water.
This will physically remove some of the ammonia, nitrites and nitrates from the water, so that it is cleaner for your fish to live in. A 20% change should be done every week in a fully cycled tank, however daily 10% changes may be necessary in an uncycled tank, until your water test readings show ‘0’. Then a 70% change should be done at least once a month, if necessary. You may need to place your fish in another container to do this.
Be aware: It will be difficult to achieve a ‘cycled’ tank (where the bacteria are able to manage the ammonia levels and nitrite levels themselves), if the tank is smaller than 10 gallons. Which means you will need to do water changes more often, to keep your fish happy and healthy, as the filter bacteria will not be able to cope alone. This will add to your weekly maintenance.
The sponge in the filter also needs to be removed and cleaned out at least once a month, (or more often if necessary). This is to remove all the gunk your filter has pulled out of the water, as it keeps it clean. Never use raw tap water to clean your fish equipment, as the chlorine in the water will kill the good bacteria that has been building up in the sponge. If this happens, the cycling process will need to start all over again, putting your fishes’ health in danger.
Always use the ‘old water’ you have taken out of your tank to rinse your fishes equipment clean.
To set up a tank successfully, you will need to:
- Organise everything in your tank as you would like it and fill it with conditioned tap water. Then, cycle it for at least a fortnight without any fish
- Test the water regularly, to check the ammonia and nitrite levels, until it is safe to put fish in – the readings from your tests should read 0.
- Add a few fish at a time and monitor the ammonia and nitrite levels to ensure they remain within safe parameters.
- Do water changes – 10%-20% at a time with conditioned water weekly or more frequently if necessary, until the cycle is complete.
- The cycle is complete when you get 6 weeks consecutively, of 0 readings from your water testing kit.
- Wash the filter sponge in the ‘old’ tank water to prevent the good bacteria being harmed.
- Only have your tank lights on for around 6-8 hours a day to give your plants chance to make their own food and grow. This will also prevent algae from growing, which can make your tank unsightly and hard to clean. Put your lights on a timer, so that they come on and turn off at set times each day.
- If you have live plants, remember that you will need to feed your plants too, every few days.
- Do not over feed your fish, as this will just give them constipation and pollute your tank.
Remember: A well kept aquarium should not smell bad, actually it should not smell at all. Happy plants, will also protect your fish and keep the algae at bay.