skimmer operation question


New member

ok, sooooooo..

what exactly am i looking for to know that the skimmer is working properly? i know that there is supposed to be yucky stuff in the cup but only a little has been accumulated.....i'm wondering if it is set right. it is set how it says to be in the book but i'm still wondering.

is the foam supposed to be close to the rim (where the stuff accumulates in the cup) all the time or should it not be in the column at all?

i've never seen one operating in person so i dont know what it is supposed to look like.

its the coralife super skimmer 65 (yes i know that it is not the most popular choice of many people on here but its what i have)


New member
I have one of these skimmers on my rock curing tank. It actually isn't a bad skimmer for the price, but it can be touchy to get (and keep) adjusted.

First question is how long have you had it running. All skimmers will take a couple of days to break in and start working. Just be sure that you are getting a heavy production of tiny, tiny bubbles swirling upward. (If not then there is a problem with the air supply or the venturi.)

When it is ready to start working you will want to tune the water level to just about the bottom of the collection cup. The tiny bubbles you are getting now will rise up to form a thin foamy layer at that level. The real action will happen above that--those tiny bubbles will start to form bigger bubbles (with more surface tension) that will then rise up the center tube on the collection cup and spill over with a thicker skimmate.

If you're getting a watery output, you'll want to lower the water level a bit with the red adjusting knob. If you aren't getting anything at all, you'll want to raise the level a bit. Don't make a big change all at once!

That leads to the one problem I've had with this skimmer (as well as two of the smaller Coralife's on frag tanks). As designed, they hang on the tank. No problem until it overflows...It has been my experience that these will be "tuned" and running just fine for days or weeks and then suddenly, they'll go crazy and just fill the cup with almost clear water.

On the 65 and larger skimmers they put a drain fitting on the bottom of the collection cup. My strong suggestion is to use it and overflow it into a gallon (or bigger) collection bottle. Either that or buy a mop.

Incidently, using the drain will not relieve you from doing regular cleaning of the collection cup. Skimmers lose efficiency as gunk builds up in that riser tube and couldn't care less how much is sitting in the cup. (You can verify this by measing the amount of new skimmate collected each day after a cleaning. The first day will be your best production and then each subsequent day will be a bit worse.)

So you'll need to shut it off, remove the cup and clean it under running water at least a couple of times a week. Every day is best.


New member
thank you so much for replying and answering. i'll fiddle with it some. its been up and running for probably a week.

i'm also wondering what skimmer would work decent with our 29/30 gallon? dont have a truckload of money to spend on one either. do i really need one for it?