See if your fish will get along before you buy them.
Pick a tank, add fish, and FishPicker checks temperature, pH, space and temperament. Then it shows you the tank, assembled.
- Pick your tankChoose a size from 5 to 125 gallons, plus the substrate and lighting you have.
- Add fish and plantsEvery fish shows whether it suits what is already in your tank.
- See the verdictYou get the problems to fix, the heater and pH to aim for, and a picture of the finished tank.
Will they get along?
Full compatibility chartBest fish for your tank size
Quick tools
All toolsStart here
All guides
Cycle your tank before you add fishThe few weeks of waiting that decide whether your fish live.
Seven mistakes that kill fish in new tanksMost beginner losses come from the same short list.
Water changes: how much and how oftenThe one chore that does the most for your fish.
Pro tips
- Test the water before you blame the fish. Most sudden deaths trace back to ammonia or nitrite.
- Buy the school, not the single fish. Six of one species look better and behave better than one each of six.
- Feed less than you think. Offer what they finish in two minutes, once or twice a day.
- Rinse filter media in old tank water, never under the tap. Chlorine kills the bacteria you need.
- Quarantine new fish for two to four weeks if you can. One sick arrival can wipe out a tank.
- Stock slowly. Add one group, wait two weeks, test the water, then add the next.