Plumbing an external pump

[iLLwiLL]

Currently my 125 has a 20 gallon sump, 2 different overflows that are prob around 600 GPH each, and 2 different return pumps - a quiet one 4000 and a rio 2100. Yes, its a hodge podge, I set it up with what I had, and am now trying to get it right.

I might be able to get an Iwaki WMD-40 rlxt, and really want to use that to replace my 2 internal pumps as I upgraded to a big boy skimmer that's throwing more heat into my tank. Only problem is I have no clue what I'm doing :spin2:

Where / how should I mount this Iwaki pump, and how should I go about plumbing it? how can i get it to not run dry if the power cuts out, then back on? will i get more flow out of the iwaki over the 2 internals I have running now? If anyone knows of any threads that may be of help, please point me in the right direction.

Thanks for any help!!

~Will.

[murfman]

The Iwaki is only 750 gph at 4' of head. The quiet one is 1017 gph at 0' head. The Rio 2100 is 692 at 0' head. I would drill the sump for a 3/4" bulkhead and plumb the Iwaki in to it for 1 return and use the QO as the 2nd return. Put ball valve on the return side of each pump so that you can limit how much water goes back in to the tank, should your overflows not be able to keep up.

Ideally, you would have 1 pump, like a dart or bigger, that acts as your 1 return pump.

[1DeR9_3Hy]

^^^ What he said :)

[CasinoHeat]

All depends on the intake of the Iwaki you want to keep the same size from the sump to the pump after that you can tone the output down

[iLLwiLL]

Drilling the sump at this point is pretty much out of the question. if it breaks i'm screwed, and i dont have or know anyone with glass hole saws. Is there any way to plumb the iwaki so it sits on a stand next to the sump and pulls water from the return section? Will it kill the pump to run dry for the 1-2 secconds it takes the water to get into it?

~Will.

[CasinoHeat]

No but how big is the sump bulkhead and how big is the input of the pump?

[iLLwiLL]

The sump is a 20 tall aquarium, there are no bulkheads. It holds an input section with baffles, filter pad and a bunch of live rock rubble, then it goes to an asm G3 skimmer, then to a return section where the rio and quiet one pumps are.

The only reason i'm looking at the WMD40rlxt is I can get it in a trade package i'm working on, so no money out of pocket. I would like to try to make it work if possible, but if its going to gimp my setup i'll pass on it.

~Will.