Ca reactor and cloudiness

[mogurnda]

I have been having this problem ever since I refilled my DIY Ca reactor. It ran for about 6 months without major problems, but recently it has been putting out a lot of fine dust that's clouding my tank. I can usually get things to clear up by flushing a lot of tank water through it for a few hours, and then turning it back down.

I think it may be that the mag 3 circulation pump is making it fluidize too strongly, and pulverizing the medium.

There are a few things I think I can rule out:
-The new medium (coralith) is from the exact same container as the original, so that isn't the problem
-The tank Ca is ~415 and alkalinity ~3.5, so there isn't a saturation problem.

Other parameters, FWIW, are:
90 gallon reef tank
NO3 <1
PO4 not measurable
pH 8.1-8.3
temp 77

I am hoping to fix it by reducing the flow using a valve on the mag 3, but I was wondering if anyone has insight on why it has started all of a sudden.

 

[chadfarmer]

did you clean the media before you put it in the reactor?

 

[mogurnda]

Yes. Plus, this has been going on for over a month, so it's not likely to be left over dust.

 

[Highlander]

Sounds like your Ph might be too low and the media is "mudding".
When was the last time you calibrated your probe?

 

[mogurnda]

Haven't checked in a while, but there's not much evidence of drift. The effluent pH has never gone much under 7.2, so I don't think it's mudding, but I will bring some calibration fluid home tonight, and also take a sample to work to double check.

 

[xinumaster]

sounds like you c02 is too strong.

 

[mogurnda]

Figured it out. Instead of using all new medium when I changed it the last time, I mixed new and old. The old stuff was smooth and small enough to fluidize easily, so it was constantly getting ground to dust. I just replaced all of the medium, and it's not fluidizing, nor am I getting the dust problem.

I guess that's why you're supposed to replace the stuff.