How To Do A Fish Tank / Aquarium Water Change
In many respects, the art of keeping fish could be regarded as also being the art of the water change. Water changes are essential when cycling a tank, and even when a tank is cycled, water changes keep nitrate levels down.
The beginner fish keeper who wishes to maintain the health of their fish is well advised to master the water change. When starting tanks from scratch, one certainly gets plenty of opportunities to practice.
- Self Starting Siphon
These only cost a few dollars and will make a world of difference when it comes to water changes. You simply put the cylinder end in the water, pump it up and down fairly furiously, and water will begin to flow through the hose. There are many difference sizes of self starting siphons available, and I heartily advise any fish keeper to purchase one. The alternative can be sucking water through the siphon by mouth, not an attractive proposition when one considers that the contents of the water include quite a number of bacteria, not to mention ammonia from fish wastes.
- A Towel
Always have a towel or two handy. Eventually you will accidentally toss some water on the floor, and you'll be more than glad you had the presence of mind to bring something to soak it up with before it sinks into the carpet.
- Dechlorinator / Ager
Prime is a good product on sale in the USA, but there are many kinds of dechlorinators on the market. You MUST use these on any water you put into your aquarium. Chlorine kills bugs and it kills fish too. Follow the directions on the bottle for dosing requirements. Oh, and buy a large bottle. You'll be using this a lot and those little bottles won't last forever.
- A Bucket
This seems self evident, but it comes with a caveat. Make sure you have a bucket dedicated only to fish keeping. No soaps or detergents should ever have been used in this bucket and it should never be allowed to be used for anything other than fish keeping related activities. Soaps, detergents and household chemicals are a no no. If your fish bucket is accidentally used for something else, get a new one.
Changing The Water
When it comes to actually performing the water change, it's a fairly simple process. Siphon out a portion of the dirty water (if you have very high ammonia and nitrite levels, a 50% change to an 80% change could be necessary depending on how many fish you have in the tank, and how hardy they are.) Normal water changes are between 10% to 15%.
The trick really comes when it is time to return water to the tank. You need to make sure that the water has been properly dosed with dechlorinator (a little too much is better than a little too little,) is at the same temperature as the water in the tank already, and is the same pH as the water in the tank already.
pH can be a big one. If you have altered the pH of your tank, you need to ensure that the pH of the water you put in is not very far off the existing tank pH. PH changes of more than one scale division can seriously stress and kill fish.
The best way to return water to a tank is the same way you took it out, via siphon. Siphoning water back into the tank slowly allows the fish inside to adjust to the new water relatively slowly, and more importantly, your tank won't be disturbed by the rushing water fall of great buckets of water being dumped into it.