Heh. These are all the parts that are done and working! I think you misunderstand a couple of things. Let me explain...
[quote author=sfsuphysics link=topic=4551.msg66495#msg66495 date=1228060340]
Ok looking at your picture there's a few comments/suggestions/warnings
1: Looks your your tank drains into "sump1" on the right side, how does that "dirty water" get to the skimmer compartment in "sump2" on the left?
-- I would probably advise you simply drain directly to your skimmer compartment.
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There's a baffle perpendicular to the other baffle that splits what looks like one section into two. Water flows into the second sump though a bulkhead below the water level. It overflows into the skimmer section, then that overflows into the return section where's it's pumped back to the first sump.
[quote author=sfsuphysics link=topic=4551.msg66495#msg66495 date=1228060340]
2: Why is there a pump in "sump2" that pumps to "sump1" ??
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There would be no water exchange between the sumps if there weren't a pump. That second pump just circulates water from the sump in the closet back to the sump in the stand. Water then freely flows from the sump in the stand back to the sump in the closet. They're at the same height so it's important that the return between them be below the water level. This also makes the return section in the closet sump be the top-off section, which is convenient.
[quote author=sfsuphysics link=topic=4551.msg66495#msg66495 date=1228060340]
-- I would very much advise against trying to use a two tier pumping system without some sort of bulkhead in place in the 2nd tier to drain excess water back to the first tier. Because there is no way you can match both of those pumps flow even with the same pump and you will drain one faster and either run a pump dry or overflow one of the sumps. It looks like you do have a connection between the two, but I don't see why you want to pump water there at all, just to add more circulation in the sump?
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There is a bulkhead that drains excess water from the sump under the stand to the sump in the closet.
There's no attempt to match flow rate. In fact, they have significantly different flow rates because the connection between the sumps can only handle a couple hundred GPH.
[quote author=sfsuphysics link=topic=4551.msg66495#msg66495 date=1228060340]
-- My advice, have your tank drain to the skimmer compartment, ditch pump2 keeping your sumps connected. Now you can go two directions, put bulkheads and connection on the closet sump high, connected to stand sump effectively making 3 compartments of your multi-part-sump (I did this myself), however you'd need to move your float switch to the sump under the stand. Or keep it the way it is without the pump2 of course with the bulkhead low to the ground, effectively making a larger compartment and your float switch can stay. I prefer the former idea because that third sump chamber gives you the option for a refugium or something.
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As I mentioned in reply to Phong's post, it's not possible to have the tank drain directly into the skimmer compartment because I'm not set up to drill a 2" hole though 8" thick brick and stone.
The only way I could do one pump would be to have it in the closet sump pumping back to the display tank. As I mentioned, though, I'm limited by the flow rate between the two sumps. I want more flow than that between the sump in the stand and the display tank. Hence two pumps.
