From what I understand a protein skimmer is not useful for freshwater. I don't have one on any of my tanks and i've never had a saltwater tank.
I would def. go the bulkhead/cap route on the holes on the bottom, that will seal them off and still allow you to use them later if you want. Covering them with glass plates will be a much more permanent repair.
your gravel will cover the caps without any problem, they make 'flush mount' screw in caps, at most the whole fitting will be 1/4" above the bottom of the tank. Visit a plumbing supply house, tell them what you're doing and they'll be able to hook you up.
Saltwater tanks usually move a TON of water to simulate oceanic currents (I guess, see above about my lack of saltwater knowledge). You won't need that much turnover for your freshwater, depending on stock levels. If you need to reduce flow to the tank its much better to put a T in on the return line and use that to split some of the water back through the sump loop instead of using a valve to slow the water which would put extra stress on your pump.
I would def. go the bulkhead/cap route on the holes on the bottom, that will seal them off and still allow you to use them later if you want. Covering them with glass plates will be a much more permanent repair.
your gravel will cover the caps without any problem, they make 'flush mount' screw in caps, at most the whole fitting will be 1/4" above the bottom of the tank. Visit a plumbing supply house, tell them what you're doing and they'll be able to hook you up.
Saltwater tanks usually move a TON of water to simulate oceanic currents (I guess, see above about my lack of saltwater knowledge). You won't need that much turnover for your freshwater, depending on stock levels. If you need to reduce flow to the tank its much better to put a T in on the return line and use that to split some of the water back through the sump loop instead of using a valve to slow the water which would put extra stress on your pump.
