Geoff skimmer overflowing

hydroman · 11-28-2005, 09:18 PM

Has anyone figured out how to keep one of Geoff's great skimmers from overflowing?

This afternoon I did a water change and adjusted the flow through my skimmer a little bit. Well, it seems I overadjusted because when I came back a short while later it was overflowing. Luckily the skimmer sits in the sump so most of the water ended up back in the sump; however, about a half gallon ended up on the floor when it overflowed the collection bucket. Part of the reason I want to figure out a way to keep it from overflowing all over is because I'm going to be building a much larger version that sits outside the sump. If that one overflows, I'll probably be shot.

One idea I've had is to hook the pump up to a float valve that would shut off when the water level dropped too far. The problem with that is that when the pump shuts off, the skimmer drains a little bit which would raise the level in the sump enough to turn the pump back on. This would lead to a rapid on/off cycling of the pump. Any other ideas floating around out there in the great collective?

I would attach a picture of my skimmer, but my camera is on the fritz and I don't have any old pictures. While it isn't quite as good, I've attached an old sketch I created when I was building it.

Thanks

Tim224DT · 11-28-2005, 09:21 PM

I have a DIY skimmer, My colection cup is a measuring cup that hangs on the inside of my sump. So if the skimmers starts to skim wet it overflows the measuring cup and falls back into the sump.

Tim

Geoff · 11-29-2005, 02:39 AM

unfortunately all skimmers can do this. as DOC levels go up and down the skimming amount can change. this is a lot more noticeable when running a wet skimmate.

one mod i have done is add a second ball valve on the inlet right next to the other one. this one allows you to set one and leave it. then when you do something that causes a sudden skimmer just you can adjust the other one. stuff like water changes and adding epoxy to the tank seem to be some of the biggest offenders.

another thing i have done is make a dump bucket. i have my skimmer cup drain into this dump bucket. this dump bucket is located right next to the sump. if this happens to overflow it dumps back into the sump. so if anything were to happen it will not flood the place.

some people make these containers airtight with a ping-pong valve in them. they then seal off the skimmers collection cup. when skimmate fills up the container the level rises. it eventually raises the ping-pong valve. this then makes the container air tight. all of this being air tight causes the pressure in the skimmer to increase. this increase in pressure keeps the bubbles from forming as fine in the skimmer. thus keeping the skimmer from overflowing.

HTH,

G~

yardboy · 11-29-2005, 06:04 AM

You just have to make sure you make the skimmer cup airtight also, but otherwise a waste collector is a marvelous invention!

hydroman · 11-29-2005, 09:36 AM

Thanks for all of the ideas. I particularily like Tim and Geoff's ideas about having the collection cup overflow into the sump. One thing I considered last night was increasing the height of the collection cup and having a 1" pipe coming off back into the sump. It would be a few inches higher than the drain into the waste container, but if it starts overflowing, it should go through the 1" line rather than overflow the skimmer. Obviously it depends on how much water is being pushed into the skimmer, but I'm running a pretty low flow. Gives me plenty to think about, thanks again.

hydroman · 11-29-2005, 09:45 AM

Yardboy- You mention making sure that the skimmer cup is airtight, are you talking about the waste collection container or the top portion of the skimmer where the foam is collected? In either case, don't you worry about an airlock increasing the pressure and preventing the skimmer from draining properly? Although, I could be completely off on my logic.

Geoff · 11-29-2005, 11:43 AM

Quote:

Originally Posted by hydroman

Yardboy- You mention making sure that the skimmer cup is airtight, are you talking about the waste collection container or the top portion of the skimmer where the foam is collected? In either case, don't you worry about an airlock increasing the pressure and preventing the skimmer from draining properly? Although, I could be completely off on my logic.

your logic is just about dead on. the drain from the collection cup will get blocked off by the rising water. this will increase the pressuer like you said and shut down bubble production. the object is to have the drain from the collection cup lower than the air hole for the waste collector. that way the water hits this tube shutting down the bubble production.

i have had so-so luck using this method. it is vitally importan that the collection cup is airtight and can handle pressure or it will not work. i use the waste collector draining into the sump for reliability. there is no reason you can not combine both methods.

G~

wharyat · 11-29-2005, 06:31 PM

Actually with the float valve collection vessle, the object is to shut off air supply to the venturi once the valve is shut so no microbubbles are produced. If the vessle and collection cup are sealed, I would see a massive amount of microbubbles making their way out.

yardboy · 11-29-2005, 08:48 PM

I stil stand by what I said, but maybe I didn't make it clear. If the skimmer cup isn't sealed (except for the drain line) then when the collection cup fills up and the float valve closes, then the skimmate will overflow the cup back into the skimmer. With the cup sealed and the float valve closed, the air has nowhere to go, the beckett stops sucking air, and the water level drops in the skimmer, due to not drawing in any air. It'll sit there with just water running through the skimmer until you shut it down and clean it out. Right before the float shuts down though, there's quite a gurgling sound as air blows by the high level in the collector, that my alarm to shut it down and clean it. Here's my MR-1 with a collection chamber. Works like a charm and I've never had it fail. Short of the tubing blowing off I don't see how it could fail.

wharyat · 11-29-2005, 09:40 PM

Oh yes, I forgot MRC made one.

I made one for my skimmer that works by cutting the venturi's air supply, that way I didn't have to seal anything. It can be done many ways.

Geoff · 11-30-2005, 02:45 AM

Quote:

Originally Posted by wharyat

Actually with the float valve collection vessle, the object is to shut off air supply to the venturi once the valve is shut so no microbubbles are produced. If the vessle and collection cup are sealed, I would see a massive amount of microbubbles making their way out.

this should also work, i have not seen it setup this way, but makes a lot of sense also.

G~

hydroman · 11-30-2005, 03:10 PM

Yardboy- Thanks for the picture, the setup you were describing makes much more sense. Thanks everyone for their ideas, this should keep the gears spining in my head for quite a while.