Sump planning stage.

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Aquarium Advice Addict
Oct 3, 2002
Highland , IL
I will be setting up my 150 gallon FOWLR, I just acquired a 75 gallon tank to use as a sump. Neither tank is drilled. I was wondering what equipment I will need to plumb this thing. I am also looking for any ideas people want to throw out there. Thanks in advance.
If you can possibly get the main tank drilled, do that. Unfortunately, a 150 Gallon tank is likely to have a tempered bottom, which is risky to drill.

Otherwise, what you need is an overflow box. The type with the U-tubes is reported to be most reliable.

For return, you want a sump pump that can handle the height diffrence and flow requirements.

My research project on the subject:
If it's not pre-drilled, as dskidmore said, drilling the bottom is a no-no. You can generally drill the back or the side panels though. Just verify that they aren't tempered also. Since you are in the planning stages, I would go with drilled as opposed to an overflow box. One thing less to worry about. Maybe plan out a closed-loop and get the glass shop to do all the holes at once :)
Also check out flexible spa hose. Glues right into PVC. Also consider flow regulators (ball valves, gate valves etc, and unions. Think about wherever you even MIGHT want to or need to service something wo you can shutoff flow or disconnect when needed. Of course, you may not need all that stuff for the setup you have in mind, but regulating input to skimmers or UVs may be useful.

Check this pic out. Maybe it can give you some ideas. Maybe not, but here it is...
Ah. So you probably had to pay more for it. I wonder if a spa/pool store might have it in other colors? I'd guess blue would match your average pool liner.
Drilling is the way to go, you will not be sorry. Check some glass stores and see how much they charge. The overflow boxes work well but there is always a chance of a flood with them and for the cost of 2 OF boxes you could have the tank drilled.
Just something to think about..
wouldnt drilling the bottom of a tank decrease its strength considering a 150 gallon and the hundreds of pounds of weight on it ?>

not to mention the price of a 150 i dunno just asking
If the bottom isn't tempered, a hole or two won't hurt anything. (Assuming it's done properly.) The ultimate would be a tank that was drilled before assembly, and the glass tempered with the holes in it.
I use a CPR overflow w/ no problems at all. If you do use a CPR overflow(s) don't use the air pump they recommend to maintain/restart the siphon. A maxi-jet 1200 ph works much better. I've never had a failure using one. If the sump, return plumbing, and overflow are set up correctly floods will not occur whether the return pump and/or overflow fail for any reason. One thing that helped me when building my sump was LxWxH(in inches)/231=Volume in gals. Also this site is a great reference for sump designs etc.-
Good luck!
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