Thinking Of setting up a closed loop on a 90 that I'm planing to buy but don't know where to start with equipment and wHere to get it drilled botom of the tank or back any info would help
If the tank is a standard 90 and not custom made the bottom will be tempered so you can not drill it. If you want to drill it yourself you can order the hole saws from glass hooles or bulkreefsupply, just get some old glass preferably the same thickness and practice first. If you dont want to drill it yourself I am sure Skiptons can for a charge.
I have a 90gal bow that I built a CL into. I came in through the back for all (CL and return) plumbing. I have an OM 4-way that cycles the CL from the upper rear to the lower front outlets. See the pics for details:
detail of intake with screens. Center fittings are for overflow and returns. CL returns are drilled into the four corners:
Ya it does look scery I think all glass 90 are not tempered cuz I wanted the inlets to come from the back and come out from under the tank but it looks like it's gona be a he'll of a project
I like having the lower-front outlets (although critters can push sand in front and casue sand storms). All-in-all it's done what I had hoped. At some point I'll likely upgrade my pump from the PW 100PX-X.