🏠 Tank Size Checker

Tell us about your setup and we'll let you know if your fish have enough room to thrive

Your Setup

Tell us about your water type, fish, and tank — we'll do the rest!

Water Type

Fish in Your Tank

Keeping more than one type of fish together? Add each one separately — e.g. 2 koi and 2 goldfish in the same pond.

Fish Type

Count

Avg Size (in)

Tank / Pond Type

Volume (gallons)

Filtration Type

Plants?

💡 Stocking guidelines vary by species. Koi need 250 gallons each, fancy goldfish 20–30 gallons, bettas need at least 5 gallons alone, tropical fish roughly 1 inch per gallon, and marine fish need generous space. Our AI uses species-specific rules for every fish type!