Lighting on a 15 gallon or 20 gallon

[kingfishson]

I have a 4 24watt t5 fixture on my 30 gallon and want to buy a 15 gallon or 20 gallon tank as a frag tank will this light be enough light or not enough or to much? for SPS on the top LPS on the middle shelf and Soft Coral on the bottom. I'm going to plumb this tank to my 125 gallon.
Also how should I plumb this tank to my sump I would like to keep this tank in my stand if possible.

 

[mariobrothersleeve]

It will be enough lighting. I wouldnt want to risk plumbing my frag tank to my dt. Thats alot of money if it fails and has a problem in one or the other.

 

[kingfishson]

Ok, thanks and maybe I wont plumb the tank in I just thought that the water would be more stable.

 

[mariobrothersleeve]

That is true, it sounds more risky than i would do.
My buddy had a set up just like this, he changed his dt from a 90 to a 150. He rinsed his sand, had a huge death with fish and went threw a ph swing taking large colonies out. It also went into his frag tank and killed them off. From this is where i seperated my system. I test my frag tank more often and run different parameters to increase growth.
In my dt, i run microalgae. My cal and mag seem to suffer from this as it wants to strip the mag out of the system, on the frag tank, the levels are more consistant for me so far. I like to manually dose my ft, to many issues imho in dosing pumps failing and incorrectly adding/not adding required amounts.