This is a guide to cleaning a fish tank, or aquarium. This is not an extremely complicated process, but a few different kinds of tools are needed and a few techniques must be learned. It will cover clean water and fresh water tanks.
Remember to always wash and rinse your hands before and after putting them into the water in your fish tank, to avoid getting nasty things into the water, and vice versa.
CLEANING CLEAN WATER FISH TANKS
Here’s how to clean a clean water fish tank:
1) The Inside Glass
Algae often forms on the inside glass of a fish tank. It is caused by an excess of nutrients in the water, and you can reduce it by feeding the fish less often and changing the water more frequently. Algae can often be helpful, naturally filtering the water. If there’s too much of it though, it can starve the water of oxygen.
You can remove algae by scrubbing the inside glass of the tank with an algae pad. Use one specifically made for aquariums, to avoid unwanted chemicals from seeping into the water. Really tough algae can be scraped off with a razor blade (or a plastic blade if the tank is made of acrylic).
2) Replacing the Water
The water in a fish tank should be replaced from time to time. Instead of changing a lot at once, which can stress the fish, try to change a little bit more often, such as 20% of the water every 2 weeks, or even 10% weekly.
Use a water siphon to pull the water out of the tank and into a bucket or pail. This water will be replaced after you’re finished cleaning.
3) The Gravel
Use a gravel vacuum on the gravel at the bottom of your tank to suck up anything that has landed there, such as food, fish waste, etc. You want the right size of vacuum- if it’s too large it will suck up too much water, and too small will take a long time to finish cleaning. You don’t need to go through all the gravel, maybe 1/3rd to half each time will be enough.
Clean your vacuum with hot water (or stronger) after using to kill any bacteria.
4) The Decorations
Sometimes you will want to clean the decorations in your tank. Mix some bleach in the water you siphoned out of the tank, and use that and an algae pad to scrape them clean. Then rinse them off fully in running water to avoid any bleach getting into your tank.
5) The Carbon Filter
You’ll want to change the carbon in your filter once a month or it will start to harm your fish. You should also rinse the filter every time you do a water change (every 1-2 weeks).
Lastly, make sure to wipe down the outside glass, hood, lights and the top of the tank using an aquarium-safe cleaner.
Replace the water you removed from the tank, using fresh, treated water at the same temperature. Leave some space at the top of the tank, so the fish have air to breathe.
CLEANING SALT WATER TANKS
Most of the same rules above apply to saltwater tanks. However, there are some differences you must consider.
Salt water fish have a very narrow range of temperature, salinity and pH they can live in. In a salt water tank you need to control these factors very precisely.
When changing water, use distilled water (this can be bought at a grocery store, or you can make your own). Heat the water to get it at the right temperature, and add a salt mix following the instructions. Let this water air overnight, and the next day test the salinity, temperature and pH to make sure they are all in the right range.
Make sure you change the water at least every two weeks, to avoid the build up of nitrates.
Check the temperature daily to make sure it stays in the right range.
Evaporated salt water will leave a residue at the top of your tank, so make sure to wipe it down consistently with an algae pad.
Good luck and stay prepared!