SearchAsk us anythingarrow rightHow many GPH does a 100 gallon tank need?So 1000 gph is suitable for 100 gallons.Let's Get It Fixed!Our virtual experts can diagnose your issue (for free!) and resolve simple problems.Chat with a live expertChat nowCall 1 (855) 466-3948Call nowRATESHARECopy linkTwitterFacebookmagnifying glassLink copied to clipboard.SUBMIT AN ANSWERShop Recommended ProductsShop HomeX Recommended ProductsRELATED QUESTIONSHow many GPH does a 120 gallon tank need?I've been in the aquariums for a while and I know that the GPH should be 5-10x gallons in the tank, however, I only received a 120-gallon tank that came with two Fluval container filters.The combined GPH total is 335.The manual says it will work well for a 140-gallon tank.How many GPH does a 30 gallon tank need?In general, we recommend that you rotate the aquarium volume four times per hour on average. This means that if you have a 30-gallon tank, you need a pump and filter with a flow rate of about 120 g/h.How many GPH is needed for a fish tank?We usually recommend turning the aquarium volume four times an hour on average. This means that if you have a tank of 30 gallons, you need a pump and a flow filter of about 120 gph.How many GPH does a 40 gallon tank need?Well, anyway, it's usually said a flow rate 5 times the amount of gallons your tank maintains is good flow to a typical aquarium. So, the 40 gallons x 5 rotate over 200 GPH flow. So you'd like a pump filter rated at 200GPH or more.How many GPH does a 75 gallon tank need?A 75-gallon freshwater aquarium must use a rated pump of at least 375 GPH (gallon per hour). A 75-gallon tank, however, will not require a pump that can produce 300 GPH.