Deltec MC500 Skimmer Overflowing

SoCalVictor · Aug 23, 2019

I have a Deltec MC500 that runs in the integrated sump area of my Red Sea Max 250. Once the skimmer settled in, I was able to open the air valve completely and it was skimming well and pulling 1/4 cup of skimmate a day.

The last few days, the skimmer keeps overflowing and even after closing the air valve 50%. Water levels are consistent and there's no noticeable changes I see happening in my aquarium.

Any thoughts or guesses on what might be happening?

Red Sea Max 250, Deltec MC500 Skimmer, Vortech MP40WQD X 2, 6x39W T5 Lighting, Mixed SPS, LPS, Softies with Fish

DeltecUSA · Aug 23, 2019

There could be a few reasons this is happening. If you recently used an additive that you hadn't used prior to the skimmer breaking in, that could cause it. How long has the skimmer been on your system? Could still be breaking in. I've used several MC500 skimmers over the years and there are a few things you can do until you're sure that the skimmer has fully acclimated or whatever is causing this has run its course. Raise the collection cup to the absolute highest point where it is just sealed on the housing. If that doesn't do it, tilt the collection cup back just slightly so there's a gap between the housing and the collection cup that lets the water drain back into the sump area. You're not going to get a lot of skimmate while doing this but it will work as a temporary fix until the situation stabilizes then put the cup back as you normally would and work it lower into the housing over time.

hth
Doug

SoCalVictor · Aug 24, 2019

Thanks for those thoughts Just figured it out. ;Facepalm

My mechanical filtration was clogged so the chamber where my ATO sensor sits was low in water while the chamber where the skimmer sits was high in water. I'm realizing that the skimmer is quite sensitive to water levels.

DeltecUSA · Aug 26, 2019

Good to hear you figured it out. There's also a weir plate that you can adjust that will set your water level in the skimmer so that doesn't happen again. Just pull it up and once the water level stabilizes you shouldn't have any more problems. If you do just pm me and I'll see what I can do to help.

Doug

SoCalVictor · Aug 26, 2019

Yea, I removed the Weir Plate when I was breaking in the skimmer and never put it back as I was producing skimmate pretty well w/o it. Is it recommended to put it back?

DeltecUSA · Aug 26, 2019

If you find that the water level in the area you have your MC500 is changing on a regular basis which is impacting the skimmer's performance, then I would use it. However, I've been using Deltec skimmers since about 2002 and typically once the water level is set they don't require any additional fine tuning.