Convert f/o tank for sump

[jeepers]

Hi, I have a 140 gallon fish only glass tank with fittings on the bottom (undergravel filter) plumbed to an Ocean Clear filter, heater and of course pump. No overflow. Only thing coming into the tank from the top are airlines. Now, I've been considering converting to a sump with protein skimmer. I'm about to build a new canopy and stand so it seems like a good time. Question is: Any way to use the 2-way fitting on the bottom of the tank? I'm thinking I need an overflow at the top in case of power outages, etc... What would you do??? Maybe I don't really need a skimmer? The Ocean Clear does a good job, I clean the pleat and put charcoal in the center of the filter regularly. I'm just figuring the OC and a skimmer is even better.
I'd like to eventually move away from fish only, but the tank is so deep ~32" that I don't know if I'll ever afford enough lighting so it's a ways off
Thanks

 

[michaeltx]

not sure what you mean by fittings but if the bottom of the tank has holes in it then you can build or buy a overflow box and take out the fittings maybe have the holes made alittle bit bigger (dont know how big they are). silacone in the overflow box and get a PVC pipe or pluming kit and the you would have a overflow.
A godd skimmer is always good to have.
HTH
and maybe someone can add somemore to help you
Mike