is 30g sump enough for 250g tank?

[kurare]

What her209 said, start if off slowly and monitor... top off as needed, and keep the sump closed with a lid if ya got one to keep the moisture evaporation to a minimum. I mean look at those canister filters, they're what 10-15 gallons large? ^^

yo bderick, nice tank i likes!

 

[nfored]

I agree with all of this, just wanted to add 10 inchs of water is the same as the water level being 10 inchs high due to the volume of bioballs. Meaning that if you need 4 inches of water to make the pump work then, it doesn't matter of its 4 inches of just water or 4 inches of water and bio media.