building a sump questions

[ccrfuzzy]

BTW, I typed something like this last night (ok, after MN so consider the circumstances. LOL) and now can't find it. Who knows where it went...

I'm resigned to building a sump/refugium tank to use as a biofilter for my 55 gal FO-for now new setup. I do have a 20 long with an overflow for w/d built into one side. IF that fits in the stand below my current tank, it's what I'll use. I'll just install a second baffle overflow on the opposite end. That part's easy.
I found the plans to build a DIY overflow in the article archive. It's the one from the about.com pages.
First question: how do I balance the amount of overflow from the tank with a return pump? Is there some basic raw figures to calculate the two? I'd gladly build the overflow first, figure out GPH and then buy the return pump if that's the ticket, but maybe you guys know another way. I'm not into reinventing the wheel here, I'm more than happy to learn from other people's "experience".
Second question: protien skimming. I certainly want to install a PS with the new sump/fuge tank. PS's have an intake and an outflow. Can I use a PS as a 'pump' to get the water into the sump instead of an overflow? i.e. water enters PS, gets treated, instead of re-entering the tank it flows into the sump below the tank, goes through that system and then returns to main tank. Is there a reason that won't work? If it would work, I'm back to figuring out return pump size again.
I'm not 100% sold on making my own PS right now unless it means I can really increase the efficiency by customizing it for this purpose. For instance, If I did use the PS as a means to transfer water to the sump, I could make the PS as long as the distance from the upper tank to the lower (~3 feet?) which is much larger than I could afford to purchase for anywhere close to the same money. Higher water column means more skimming efficiency, right?
Am I in the right ballpark here or buying trouble. I dont' need to buy trouble, I can get plenty for free all by myself.
Elaine

[Woodstock]

how do I balance the amount of overflow from the tank with a return pump? Is there some basic raw figures to calculate the two?

The return pump will determine the overflow amount... the overflow size and sump size should determine which pump you purchase.

Can I use a PS as a 'pump' to get the water into the sump instead of an overflow? i.e. water enters PS, gets treated, instead of re-entering the tank it flows into the sump below the tank, goes through that system and then returns to main tank. Is there a reason that won't work? If it would work, I'm back to figuring out return pump size again.

No. Gravity will take care of the water flowing into the sump. The amount of water flowing down will be determined by your return pump. For example, a return pump that pushes 500 gph at 4' head will not only push 500 gph back up to your display, but will also cause 500 gph to flow through your overflow and into your sump.

I'm not 100% sold on making my own PS right now unless it means I can really increase the efficiency by customizing it for this purpose. For instance, If I did use the PS as a means to transfer water to the sump, I could make the PS as long as the distance from the upper tank to the lower (~3 feet?) which is much larger than I could afford to purchase for anywhere close to the same money. Higher water column means more skimming efficiency, right?

I would invest in a proven protien skimmer.

[Yarr]

higher water column = more efficiency.. not really.. all comes down to contact time that the waer has to the bubbles.. and the smaller finer bubbles are the ones u want. that is the main thing with a skimmer in my opinion.