Plumbing 2 90 Gallon Tanks...

[Stuart McCowan]

together??? I just got a brand new cpre-drilled corner overflow 90, I also got a steal on a used 90 gal with a pre-drilled corner over flow...The new 90 I will be the display tank, the used tank I want to use as the sump, with a majority of the live rock and a DSB...but not directly underneath...I want to plumb them together so I don't have to have an intermediate tank acting as another sump. Right now I have the used 90 partially setup with it dumping into a partitioned 40 gal with the return pump and the skimmer working from there. Anyone have suggestions???

 

[wetworx101]

Yes, you will need a third tank to act as a sump. You might be able to plumb them together at similar levels (one would have to be a little higher than the other, which would have the pump in it), but the problem would be a very limited flow between the tanks. The difference in water levels would limit pressures inside the overflow pipes and only allow, if you are lucky, a couple hundred gallons per hour. A third tank as a sump, both tanks overflowing into, and pumps inside of going to each tank, would be your only good way. Make sure your sump has enough capacity to handle all the water from both tanks that would continue to flow after a powerout/pump turned off. I wouldnt go with less than a 55g for this.