wet vs dry skimming

Atleast I didn't post the video. :lol:

Dude I can't even pour it down the toliet while my girl is awake.
 
i run mine in between dry and wet...i raised the water level, i added new 12 needlewheel inside the pump and then added a valve to adjust water level, now my skimmer is pulling out like the 2 posts above but when it goes for 2 days it turn to a rich dark brownish green liquid in the collection cup..but since theres 2 collection cups all the nasty hard foamgoes to top and the liguid goes to the secondary lower collection cup.i dump mine every other day, sometimes everyday depending on if i feel like it....im using a berlin turbo, - i upgrated it...
 
<a href=showthread.php?s=&postid=6969153#post6969153 target=_blank>Originally posted</a> by NoSchwag
That's because you are not letting stuff break down. <--- that's a dry joke.. get it, dry?

Nothing breaks down and goes back into your tank in dry skimming. It doesnt just magically migrate back down from the foam into your tank.

On either method, once it gets stuck to a bubble, its gone, period. Its not affecting your tank sitting on top of a collumn of foam, and its not affecting your tank in a bucket of watery skimmate.

They are both the same as far as initial export goes.

As to longevity, wet seems better to me, simply because your neck stays cleaner, and a dirty neck ruins skimming performance.
 
<a href=showthread.php?s=&postid=6969042#post6969042 target=_blank>Originally posted</a> by ckfazz
jeffbrig - Could you explain this a little further? I don't understand how the reaction time would not be affected by wet skimming since your water column is higher in the main body of the skimmer and then almost immediately entering the collection cup.

With dry skimming, the reaction time in the water column is longer due to the foam taking longer to move to the collection cup. Also, would the foam being produced create a second contact "zone" since it is still touching the water column?

Sure. I feed my skimmer with a constant flow of water (it's a recirulcating skimmer). If I feed 300gph throug my skimmer, which holds 10g of water, it turns over 30 times per hour. That means a dwell time of ~2 minutes. Elevating the water/foam level by restricting the output has no significant effect on the flow rate, so dwell time is essentially unaffected.

If you wanted to argue that it has an effect, it would actually slow the feed rate, increase the overall volume slightly, which would actually increase the dwell time. Still, it's not enough to be significant.

To answer your question, I don't think holding a head of foam has anything to do with skimmer performance. Organics are attractic to clean bubbles, the smaller the better for more surface area (everyone can agree on that). Once you've bound an organic to a bubble, it's done. Get it to the top and get it out of there. Keeping the bubbles and foam at the top doesn't have a magnetic attraction to collect other organics. They just pile up due to more bubbles rising and popping.

Bottom line for me is that wet skimming keeps the skimmer neck cleaner, which makes for better performance between cleanings. If I run my skimmer dry, the foam level will drop as solids build up at the top of the skimmer neck. If I leave it like this for several days, eventually nothing makes it into the cup. On the other hand, if I run wet, I get a consistent skimmate each day, and the cup requires less cleaning when I go to dump it.
 
ckfazz the reason that dry skimmate is darker is because it is more concentrated in organics, so yes if you had the same volume of wet skimmate and dry skim then the dry would have removed mroe organics, but what happens when you wet skim you remove more volume over a shorter period of time, so in theory the increased volume will increase more overall organics. It also helps removes larger debris that would usually settle out in the more dry foam.
 
I am also not trying to start a heated debate in anyway. Just trying to have a discussion, and clarify my understanding of the two. I'm by no means an expert and I am not trying to be one. So please feel free to post your opinions as well.
 
so i guess my wet/dry theory is perfect then, get lots offoam with excess water waste also being removed...cool...i run both wet/dry.....lol
 
yea, i personally don't like to get too dry because of smell and how nasty the skimate can get....just something else to consider
 
well you can always add carbon too to rid smell , my berlin has an extrajust for that purpose, actually thinkin on using it...
 
<a href=showthread.php?s=&postid=6970211#post6970211 target=_blank>Originally posted</a> by RichConley
Nothing breaks down and goes back into your tank in dry skimming. It doesnt just magically migrate back down from the foam into your tank.

On either method, once it gets stuck to a bubble, its gone, period. Its not affecting your tank sitting on top of a collumn of foam, and its not affecting your tank in a bucket of watery skimmate.

They are both the same as far as initial export goes.

As to longevity, wet seems better to me, simply because your neck stays cleaner, and a dirty neck ruins skimming performance.

I'm not saying that the dry foam will break back down into your tank, I'm saying that the dry foam wont remove particulates that break down in your tank.

"once it gets stuck in the bubble" is the key phrase.

Nothing gets stuck in these bubbles.. Once it does, it's ripped out of the tank, not bubbled over the side of the collection cup.

dsc031056rz.jpg
 
It's like boiling water at the top..

The best part is that my skimmer will stay like this and the neck wont dirty up that much.

You can tell when the skimmer needs to be cleaned because you end up raising your water too high to keep the same head.

After I cleaned my skimmer today I had to turn my water down with the gate valve almost 1/4 turn!

I'll post a picture tomorrow night if I remember.
 
jeffbrig - thank you. That helped to clear up some of my confusion and I think that I understand a little better now

rottface4 -
if you had the same volume of wet skimmate and dry skim then the dry would have removed mroe organics, but what happens when you wet skim you remove more volume over a shorter period of time, so in theory the increased volume will increase more overall organics.
In this theory, wouldn't the wet skimmate be more diluted due to the increased volume of water left in it? If so, then you would actually be pulling the same amount of organics with either method, correct? For example, wet skimming is pulling 1 cup of skimate per day that contains 1/2 a cup of organics. Dry skimming is producing 2/3 cup of skimmate that contains 1/2 cup of organics. In this theory, they are both pulling the same amount of organics but in a different volume of water. My theory is probably completely off but it is how I am beginning to understand this. It seems like the only advantage, which is a decent one, to wet skimming is the maintenance of the skimmer.


NoSchwag - How would the particulates break down in your tank if you are dry skimming but not if you are wet skimming? The same water is entering the skimmer through either method which woud mean the same organics are entering the body, being collected by the foam and deposited into the collection cup. If you have a high load of nutrients in the tank, both methods would "react" to pull the excess out of the water column. This is one of the major things that is confusing me.
 
NoSchwag - How would the particulates break down in your tank if you are dry skimming but not if you are wet skimming? The same water is entering the skimmer through either method which woud mean the same organics are entering the body, being collected by the foam and deposited into the collection cup. If you have a high load of nutrients in the tank, both methods would "react" to pull the excess out of the water column. This is one of the major things that is confusing me.

Dirty, big, dry, slow bubbles don't remove particulate matter like little methed out bubbles popping at the top of the collection cup. It's all about particle skimming.

Maybe you need to see a becket running wet to understand.

Let me post a quick video if you want to see. I just cleaned my skimmer so you should be able to see it pretty good.
 
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This is pretty much what I consider to be my skimmer running perfectly at 100%. I have been playing around with it a lot to see what setting removes the most crap, and comes back the quickest after feeding.

http://s54.yousendit.com/d.aspx?id=26WI6YZ33TGYV2ZPE2UGN79GPJ

I have no idea what it pulls out because there is nothing floating around in my tank and the water is crystal. But I can tell you whatever it is, it smells like sheet.
 
Jeff, yours look right to me. It seemed to me NoSchwag was pulling out very clean water or was that just my imagination?
 
Looked like drinking water in NoSchwag's.

I skim somewhat wet for the same reason RichConley does -- don't have to clean the neck as often. It works fine for me wet or dry. I also don't really enjoy cleaning a week's worth of dry skimmate sludge it really smells bad compared to poop tea.
 
it looks like drinking water because I cleaned it and a little spilled over before I had a chance to re-adjust it. The important thing to look at is the collection cup, see all of the splatter?

That is wet skimming.

Heres what it will look like a few days later..

91795reflecphlemywtskim.jpg
 
Hmm, regarding dwell time:

If you are wet skimming then you had to raise the amount of water in your skimmer chamber, right?

If you raised the water volume in your skimmer, then the average molecule is taking longer to exit the skimmer, right?

But as far as not having to empty or to clean the neck as often, if I don't clean the skimmer out every few days it starts to stink up the house.
 
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