circulation pump question


New Member
hey guys i bought a 800 gph circulation pump for my 20 gallong long reef tank is that too strong for my tank or is it manageable for my fish and some of my corals


Is this a circulation pump for filtration or a powerhead for creating in tank folw? What kind of corals?

800GPH is towards the too much end of the spectrum for internal flow in a tank that size. The general rule of thumb for in-tank flow is 20-40x tank volume. If this is for flow inside the tank then you would be better served by having multiple smaller pumps at opposite ends of the tank to create a more chaotic water movement pattern which will also cut down on low flow/dead spots.