Jbj nanocube.... How much water?

[Blitz99]

In the back, how high should water levels be in the outer chambers with the pumps?

[soulpatch]

Depends on the filtration setup and the type of equipment you have back there. I tend to run pretty darn full filling so much that the water runs over my intank media filter without going through it. Then I drain water slowly until it goes into my intank rack without spilling over it.

I totally ignore the min/max levels on the back of my tank (I have a coralife and not a jbj)

Just be careful if you put a skimmer back there that if power goes out you are not flooding your skimmer and defeating the purpose of it if you set the water levels lower...