i just set up a cube tank to get the bubble tips out of the 90 gallon. its 24 x 24 x 24, and 1/2" glass. I have it tied into my prop tank. they are cool little tanks. I am using a diy 150 watt 10K HQI.
If you do build the tank using acrylic go with a cell cast sheet, not extruded (i would use 1/2", thats just me though i guess
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