Do not: Add too many inhabitants because this often causes relationship and hygiene problems.
Do: Change the water (25 - 50%) in the aquarium every week to three weeks depending on how many and which type of fish you have.
Do not: Have your fish live in filth that they cannot escape because this often leads to death or disease.
Do: Feed your fish what they can finish eating in three minutes.
Do not: overfeed your fish as uneaten food will increase the ammonia levels in the water and lead to disease or death.
Do not: add friends who will quickly outgrow their home. (Oscars, common plecostomus, bala sharks, etc.)
Do not: house bullies with sweethearts.