Hello, fx4 is about 700gph, the 704b is 525gph. The fx can handle 150gal comfortably. The sunsun can a 100gal. This is going by the standard of a canister filter handling 4-5x water volume of tank an hr.
So if wanting to run the fx on tank I would move all media including sponges & floss from sunsun to fx & run this way for a while. Once tank is reestablished then slowly replace to media of choice.
You may lose some bacteria during this process so I also suggest you test for ammonia & nitrite during the next few weeks just to be safe. Hopefully this helps!!!!!
Originally Posted by davidwolf
I'm currently running the Sun Sun HW 704b canister filter on my 115-gallon tank. I was thinking about buying an additional filter to add with the Sun Sun but My wife bought me a gift FX4 canister that dose 250 gallons.
Do you think the fx4 is an upgrade?
If so what's the best way to switch filters Without shocking my tank.