I know it is often encouraged that one use a dedicated pump for their scrubber, but I am running out of electrical real estate and I don't think my landlord would appreciate an overhaul of the wiring. So, I'm hoping that this is a good idea and that I can get some good insight into the whole thing by asking those who've already tried this. So, the plan is to feed the scrubber via the overflow. I know that the potential for clogging is a problem, but the new system I'm setting up (after being out of the hobby for about 8 months) will have a speed drain-style overflow. There will be 2 drilled bulkheads in a single corner overflow box. There will be a ball valve on the scrubber, allowing the water level in the overflow to rise to a certain, controllable level. As a safeguard, the extra unobstructed bulkhead fitting will be there to prevent any potential disasters if the scrubber were to clog and back everything up.
The system in question will be a 40g breeder that I had before. I'm looking at a roughly 7-8" length of screen and about 8" or so tall, which should be more than covered by the added flow from the speed drain. I'm using a nice Tunze silence pump (the 600gph one, I think) that I had throttled on my previous small setup. I'll be using the previous little clamp-on fixtures and 40w CFLs that I had brand new in the box. This one will be a bit more modestly sized compared to my previous one, which was on the same tank. It did a little too well and I couldn't keep up with enough food to satisfy the needs of the scrubber.
So, any input would be greatly appreciated. Please let me know if this is feasible or at least sounds reasonable, as well as any other tips, critiques, etc. In the meantime, I'll be looking at some of the designs so that I can implement some better splashguards, ease cleaning, etc.