Cleaning a Tank
I will start by saying this is for a fresh water tank and I’ll describe it for an Oscar tank as if you can keep them clean you can keep anything clean.
Keeping the water good is your first and most important step in healthy fish keeping and tank size apart, starts with filtration.
The minimum recommended amount of filtration are:
Canister filtration should be tank gallons X 5
Hob’s or internal filters should be tank gallons X 10
If you use a combination then some recommend tank gallons X 7.5 , but my personal choice would be aim for X 10.
Having your filters sorted out and your tank cycled then we are down to your tank cleaning maintenance schedule.
Cleaning out filters will be down to type and media but a general rule is watch for a drop in output or it becomes noisy and it’s time to clean them, never change all your media at once and clean any pads, media in old tank water or dechlorinated water to preserve your bacteria colony, if you run multi filters then clean them at different intervals.
You should replace a minimum of 30% and up to 70% of your tank water each week to keep your nitrates below 20ppm (less is even better) and the best way to do this is with a gravel vac, (many brand of different sizes and shape are available).
This is a device that uses the siphon method to draw water from the tank and at the same time lift loose waste from the gravel, keeping the gravel looking clean and removing rotting material that will pollute your tank. Many use the Python
Start by turning off your heaters and waiting a few minutes until they cool to prevent them breaking, close canister valves and switch off filters at this time too as this prevents losing siphon to canisters and allow waste to settle on the bottom.
With gravel you can slightly push your gravel vac into it to get the lower waste and move the gravel a bit to release any gasses trapped, with sand you will have to play around with the distance up from the sand so as to lift the waste without lifting sand and to remove any gasses trapped you will need to stir the sand manually or use snails that burrow into it to keep it moving.
Obviously with any large décor in the tank then not all areas will be accessible, but if you do the majority of the gravel you should manage to stay on top of things and if like me you like to rearrange the décor every few months you can do a more thorough job then.
When replacing the water, remember to add your water treatment to remove any chlorine/chloramine and try to have the water as close to tank temperature as possible.
With the filters turned off it is safe to add your water treatment directly into the tank before refilling, once filled just open filter valves and switch them and your heaters back on.
Cleaning the inside of the glass has many methods, from magnetic algae cleaners, scrapers, to doing it with your hands in the water with a cloth or sponge and is a personal choice and the only thing I have to warn about is never use a cleaning agent/detergent in the tank.
Cleaning the outside is a matter of being careful with cleaning materials and sprays are to be avoided.