View Full Version : Getting a massive calcium buildup in sump!!!! Help please!

03/11/2012, 09:23 AM
I was looking for a solution to calcium buildup in my sump from two part. I had been dosing two part in the drain area of my sump for the past few months. I just recently switched to dosing pumps, but am still fine tuning the amount they are putting in. My problem is that dosing into the drain area of the sump is leading to alot of calcium buildup on my skimmer and skimmer motors. Yesterday, it took me 1 hr to get about 90% of the buildup off of the motors. The deposites were so bad that the skimmer was running at decreased efficiency and having startup issues if I shut it off. By my water parameters there should be no issue with calcium precipitation. My water is running an alk around 8.5, Mg at 1350, and calcium at 400.

Is this avoidable? Where do you put your two part into the tank? How often do you soak your motors to keep them clean?

Randy Holmes-Farley
03/11/2012, 09:47 AM
yes, it can generally be avoided.

What two part are you using?

How fast is it added and how much are you dosing each day?

How flow is there through the area (not turbulence, but in and out flow that brings in fresh water to dilute it).

03/11/2012, 09:56 AM
I am using BRS two part. When I was hand dosing I was putting in about 60 mls twice daily. So it is now being added much slower, about 6 mls per hour over 4 minutes. When I was hand dosing the 60 would be added over 3 or 4 minutes. It is a high flow high turbulence area. I was adding it right where the drain for the tank is. The drains do about 600 gallons per hour. I was dosing off to the side of this, so it could be lower, but where is am dosing is right next to the skimmer water outlet.

I think it may be best it I get more tubing (may dosing pump tubing needs replacement anyway), and make it longer so it goes into the baffles bewteen the drain and return area.

03/11/2012, 12:37 PM
^^ that is a much better place to dose 2 part.

Randy Holmes-Farley
03/11/2012, 04:28 PM
It is the alk part, not so much the calcium part, that likely leads to most of the precipitation.

If you switch to Recipe 2 based on unbaked baking soda, the pH rise is much less and the preciitiation will be less. Also, slower dosing (more spread out) will help a lot, as will making sure magnesium is not low. :)