Choosing Compatible Fish for your Aquarium

Welcome to the Compatible Fish Guide! This website lets you select combinations of fish and then provides compatibility information about your selections. Let's get started!

• Select Saltwater or Freshwater
• Select your fish
• Check the chart to see how compatible your tank will be
• Add and remove fish until you have the perfect dream aquarium!

Key Points to consider when selecting fish that get along

Behaviorally Compatible Fish

The goal of a communal tank isn't necessarily to pick out the most peaceful species, but rather to pick out fish that have complimentary and/or tolerant behaviors with each other. Many species will become aggressive and territorial to fish of the same type or in the same species group. That is why "caution" may appear for a majority of fish types when considering putting multiples of the same species. An exception to this rule is when fish typically exhibit schooling (shoaling) behavior.

There can be peaceful communal tanks, predatory fish tanks, regionally separated semi-aggressive tanks and a whole range of specialty tanks. Our app is meant for general compatibility during the early stages of picking out your fish.

Size

Size matters! A typical rule to follow is to find fish of similar sizes. It's also importan to keep in mind that the fry likely sold at the pet store are youngins and may start off similar to other species but can wind up magnitudes larger or smaller than their tank mates in the near future. When significant size differences occur, the little ones sure start to look like snacks for the bigger ones even in the case of peaceful fish.

Room in the Tank

This ties in with size, but thought it worth mentioning in its own category. There are a few guidelines around this topic and actual ideal scenarios depend largely on a combination of factors rather than a simple number. The general rule of thumb is 1 inch of fish per gallon (or about 2cm for every 3 liters).

Keep in mind, open water fish may benefit from more space and will require less obstacles where as fish that tend to hide or claim areas of the tank will need decent hiding places that they can call their own. In the case of territorial fish, proper amounts of 'homes' and space enough to prevent constant battling over regions can be just as important as inches of fish per gallon

Other Considerations

Water Temperature, diet, water type (pH & hardness, salinity, etc), tank regions (top, middle bottom), plants, coral and open space, and more!

It is always a good idea to talk to your local pet store employees and ask them for more details regarding any of the key considerations for setting up that perfect tank. There is a lot to consider when setting up your perfect aquarium, but the journey is worth it! So what will it be... a saltwater aquarium or a freshwater aquarium?