Skimmer valve/foam question

JMorris271

New member
Hi RC.
My skimmer is gushing foamy/clear water that spills over very quickly with the gate valve half way opened.
It flows a good bit of foamy water at a much slower rate with the valve closed.
I was thinking I would get a dry skim with the valve closed.
The water in the system is clear with no algae growing yet.
Shouldn't closing the skimmers gate valve kill the skimmer discharge or at least produce skimmate? I would like for the skimmer to start skimming asap-.
Thanks for your help.
 
Closing the valve will cause the water level to rise (wetter skim/overflowing) as water cannot drain from the skimmer fast enough..
 
pix of events

pix of events

closed1.jpg
The above shot is where the valve is all the way closed and it overflows.

The shot below is with the valve all the way opened.
flood.jpg

Should the velocity be that large in either situation?
 
Should the velocity be that large in either situation?

Absolutely not.. obviously

What skimmer?
What pump? (oem pump or aftermarket)
Is it in the recommended water height..
Anything else we should know. added any chemicals lately?
Has it ever worked?..
cleaned lately?
What changed? ,etc...

And did you mean closed it overflows like crazy.. open it doesn't as bad?
 
Absolutely not.. obviously

What skimmer?
What pump? (oem pump or aftermarket)
Is it in the recommended water height..
Anything else we should know. added any chemicals lately?
Has it ever worked?..
cleaned lately?
What changed? ,etc...

And did you mean closed it overflows like crazy.. open it doesn't as bad?

This photo was taken 4 months ago. I was cleaning it every 2 days because of gha and cyano
Now the DT water and sump is clear with 5 fish in the tank and no algae to speak of.

20160124_112514.jpg

This is a RO Classic 150 NWB Aquatrans pump Water is at 8 inches
2 weeks ago I added a dose of Chemiclean and 48 hrs I did a 33% water change.

That closed shot above is where that valve is closed all the way as far as it can turned.
 
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The current photos when compared to the 4 month old photo clearly show the water level in your sump is at least 2" higher than before. Either lower the sump water level back down or build a stand to raise your skimmer a few inches.
Open the valve all the way and when it settles in slowly close it till you get the desired skim.
 
The current photos when compared to the 4 month old photo clearly show the water level in your sump is at least 2" higher than before. Either lower the sump water level back down or build a stand to raise your skimmer a few inches.
Open the valve all the way and when it settles in slowly close it till you get the desired skim.

yup.. certainly a different water level there and likely the issue..
 
I don't think 8" is too deep for an nwb 150. I'vw run mine at that depth.

Chemiclean can deff make it overflow, even after a water change. If it was running ok before, I'd run it with the valve wide open and just keep dumping the cup. You may find that after 5 dumps you are back on track. It might help to pull out 5gal of water from your system (with the ato off!) to lower the water level a bit, or temporarily raise the skimmer.

Basically the more open the valve, the dryer it will skim - but when there's something in the water making it foam, all the way open is still too wet. If I read your posts right you need to skim real dry for a while so as to get as much of the chemiclean residue (and idk probs the dead bacteria that it created) out, without losing too much water along the way. Then once that stuff is removed you should go back to normal, but until you get it out the skimmer will overflow

Also, maybe check there isn't a dead snail or something inside the valve that is not letting water out even when it's open. If you don't think it's the chemiclean.
 
I have the same skimmer, 8" is a good depth, right on target according to the manual. I would check and make sure nothing is plugged first. It looks to me like it is foaming excessively, looks just like break-in...maybe added chemicals or did you happen to completely clean the unit?
 
I don't think 8" is too deep for an nwb 150. I'vw run mine at that depth.

Chemiclean can deff make it overflow, even after a water change. If it was running ok before, I'd run it with the valve wide open and just keep dumping the cup. You may find that after 5 dumps you are back on track.
The cup fills up in about 5 or 6 sec. Please believe me when I report this,I am not exagerating this. I have a video but can't get it to load so you
could see what I mean.
Any idea why the cup can fill so quickly with this valve all the way closed?
Closed is all the way down. Correct?
 
Yes, closed is all the way down. And thats why it's filling so quickly. Your thinking about it backwards. You need to OPEN the valve all the way. Turn it counter clockwise all the way.

The way the valve works is by controlling the flow of water OUT of the body of the skimmer. Not by controlling the amount of water pumped INTO the skimmer. By closing the valve completely you are forcing all the water to exit the skimmer through the top.
 
Thanks for clarifying that for me. I am just looking for fair to middle so the water runs right. That would be just a crack opened feeding the skimmer.

OK. I have pulled the skimmer out and cleaned it. pumped out 35 gals additional water change and will lower the skimmer water level to 7 inches. Hope that works
 
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The current photos when compared to the 4 month old photo clearly show the water level in your sump is at least 2" higher than before. Either lower the sump water level back down or build a stand to raise your skimmer a few inches.
Open the valve all the way and when it settles in slowly close it till you get the desired skim.
Did you see this post??

I don't think 8" is too deep for an nwb 150. I'vw run mine at that depth.

I have the same skimmer, 8" is a good depth, right on target according to the manual.
Not all systems are the same and what works for you may not always work for everyone else. The 4 month old comparison and the current photo should illustrate that but I will agree, the chemiclean is certainly having an impact as well but for the meantime lets see if we can get it settled down as quickly as possible.



The cup fills up in about 5 or 6 sec. Please believe me when I report this,I am not exagerating this. I have a video but can't get it to load so you
could see what I mean.
Any idea why the cup can fill so quickly with this valve all the way closed?
Closed is all the way down. Correct?

I do believe you because when the valve is CLOSED water has no where to go other than out the top of the skimmer. OPEN the valve all the way (counter clockwise) raise the skimmer so its sitting in about 6" of water and see what happens.
 
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Did you see this post??



Not all systems are the same and what works for you may not always work for everyone else. The 4 month old comparison and the current photo should illustrate that but I will agree, the chemiclean is certainly having an impact as well but for the meantime lets see if we can get it settled down as quickly as possible.



I have turned the valve both way to see what happened. The water overflows in secs. no mater which way I turned it. All the way opened or all the way closed

I do believe you because when the valve is CLOSED water has no where to go other than out the top of the skimmer. OPEN the valve all the way (counter clockwise) raise the skimmer so its sitting in about 6" of water and see what happens.
Yes I did see that very helpful post.And thanks for catching that.
I'm going to start out at 7 ". Drs. Foster/Smith lists that level at between 6 to 7 3/4 inches. We'll see. I need to get this right because I would love to get some corals in the tank.
 
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FWIW, I run both a classic 110int (30gal dt) and a prime 150int (new 80gal dt system I just started). Both are reef octo skimmers and the 110 sits in 5-5/8" and the new 150int sits in 6-3/4" The 110 has been rock solid for two years now and the 150 even though it is less than 2 weeks old has been doing exceptionally well, with that said I will likely raise it another 1/4".
As mentioned above I'm sure the chemiclean is a major contributor to your problem and raising the skimmer a little further will likely help till the cc is out of the system.
As for the good Dr's recommendation and even the manufacture, these are typical and not set in stone, finding the right depth to run a skimmer is key to getting the best results even if your slightly out of the recommended range.
 
I had to remake the stand and the skimmer is now sitting at 6 ". I hope that this works because i don't want to have to do it again. The drums are rolling.
 
Your water viscosity it too high. There's a billion people who will talk about the depth it sits, how far this or that is open, etc. Fact is when skimmers do that the viscosity is too high due to additives, lack of water changes, too much mechanical filtration, so on and so forth - 99% of the time.
 
Thanks Aboutacans
Well as of this point in time I have done an 80 percent water change over 2 weeks time and usually change out 30 gals every 2 weeks. No additives used but salt, the only filtration I have except for a sock is the rock. The only treatment I have used is the Chemclear to help with biopsis which is why I have done the 80 percent in the first place.
Viscosity. Would that be the same thing as the desolved organic compounds on the surface?
 
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The list is SO LONG that it probably has no end lol The big 3 are a 25% water change, which you've done. Then I remove any and all mechanical filtration. Lastly it's the skimmer trying to bubble off old chemicals that were laying around. New skimmers are extraordinarily powerful. And there's always that 1% of something else might be causing it; but the other 99% of the time it's because the new skimmer is trying to push out something that made the water viscous that the old skimmer wasn't getting.
 
It seems to me there would be better bubbles in the skimmer if there was more crapola or viscosity in the water that will produce a thicker bubble.
 
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