Overskimming?

Have an eshopps s-300 Sno cone skimmer rated for 300 gallons on a 75 gallon with a 55 gallon sump. Heavy bio load. Any potential issues?
 
Dont believe in over skimming, dont think the word should exist. What you have is oversized, but it wont pull anymore or less than any other skimmer. It will pull what organics you have.
 
A skimmers performance is dependent on the size of the skimmer relative to how dirty the water is. A certain amount of dirty water is what's needed for a skimmer to work properly.

For example, put a broken in skimmer in a brand new tank with no organics and it will not produce a foam head. Depending on the size of the system, you could dump X amount of phyto in and it still won't produce a foam head. But add Y amount of phyto in and it will suck Y right out.

The problem and what I believe is a poor standard/advice in this hobby is oversizing skimmers. I think it's best to match the manufactuers skimmer rating to the tank size and bio load. This will give you constant and more efficent performance.

With a skimmer rated for a 300 gallon system on a 75 gallon tank I think you'll find that the waste will have to build up in the system before the water is dirty enough to produce an effective foam head for removal. Once that amount of waste has been removed the head will subside until the cycle repeats. The problem here is now you may have an increase in nutrients because the skimmer never removed them before they broke down into NO3 and PO4.

I would sell the skimmer and get one that is rated for your tank size and bio load. Just my opinion. ;)
 
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A skimmers performance is dependent on the size of the skimmer relative to how dirty the water is. A certain amount of dirty water is what's needed for a skimmer to work properly.

For example, put a broken in skimmer in a brand new tank with no organics and it will not produce a foam head. Depending on the size of the system, you could dump X amount of phyto in and it still won't produce a foam head. But add Y amount of phyto in and it will suck Y right out.

The problem and what I believe is a poor standard/advice in this hobby is oversizing skimmers. I think it's best to match the manufactuers skimmer rating to the tank size and bio load. This will give you constant and more efficent performance.

With a skimmer rated for a 300 gallon system on a 75 gallon tank I think you'll find that the waste will have to build up in the system before the water is dirty enough to produce an effective foam head for removal. Once that amount of waste has been removed the head will subside until the cycle repeats. The problem here is now you may have an increase in nutrients because the skimmer never removed them before broke down into NO3 and PO4.

I would sell the skimmer and get one that is rated for your tank size and bio load. Just my opinion. ;)

+1

Your skimmer will not be consistent on your size tank. You won't have a heavy enough bio load in tank that small to generate enough dissolved organics to keep the skimmer happy. In otherwords, you skimmer won't be able to generate a good foam head. Foam fractioning requires dissolved organics and skimmers are typically sized based on theoretical bio loads and presemed levels of DOC's. Instead, what will happen is that the skimmer won't produce anything let alone decent foam until the waste builds up in the tank. Then it will skim for a short while until it peters out again until the waste builds back up. You will end up having to tune it really wet to the point that you will be starting a new thread here asking why your skimmer keeps overflowing.

I'm with Cuzz.. Sell it and get a properly sized skimmer.

P.S. Overskimming is a myth but certain corals do prefer some organics in the water.
 
I have experienced this firsthand. I had an MSX-250 on a 100 gallon tank. I was lucky to get a foam head once a day on the skimmer. Otherwise it just bubbled like freshly poured soda.
 
I'm using BK SM250 in 120G, wet skim(BK SM was designed for wet skim), good foam and never overflow. (2 years till now)

I don't believe overskimming myth.
 
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