Using Two Part - residue build up

[Husky_1]

Hey Everyone,
I am sure this has been asked, and gone over buy I could not find any information by searching. I have been dosing two part via a pump for about 3 months now and am getting a lot of buildup/sediment in my sump. Its almost like salt creep under the water. It happens in the same area as my Alk drip is going to.

Anyway, about 1.5 months ago I noticed the buildiup starting, but I also noticed that my calc line somehow ended up in the same area as the alk drip line so I moved the calc to a location in the sump "upstream" of the alk. At this point I did not think much about and wrote off the build up to both parts being dumped in the same area. Well last night, I turned off my return pump for some feeding and it would not restart. So I started messing with the pump and could barely take it off of the bottom of the sump, of course there was a little build up in the impellers that I cleaned off. I should note that because of my setup I cannot really see my return chamber so this is why I did not notice it earlier.

I should also mention that I dose kalk in my ATO reservoir. So basically my setup goes like this - Calc drip in my fuge area of the sump, then in the baffles that ATO with Kalk, then in the return I have my Alk Drip.

My current alk/calc levels:
405 calc, 4 meg/dl for alk.

So here are some of the questions I have:

Do you guys that dose via a pump have this problem, and if so what do you do to circumvent it?
Could this be caused by the Kalk?
What do you think the build up is the calc, alk or a mixture of both solutions?
Am I overdosing, and its precipitating out just in this area? I am not sure that this is the case because I have had higher levels of calc/alk in the past. My numbers are not all that high.
Basically I am just trying to prevent waste or build up in the future.

Thanks,

[Husky_1]

Oh, as far as how much I was dosing:
I am using an innovative aquatics set to run about 12 hours per day, at about 6ml per hour for each of the two parts. The pump itself is set to 18ml/hr, but because its a 1 into two setup the effective amount for each tube is about 1/3 of amount programmed.

Oh, and if this matters, my Mag is at about 1325.

[Randy Holmes-Farley]

I can't see any obvious problems with that setup. How much flow moves through the sump? More would likely lessen the problem.

Check this recent thread:


http://reefcentral.com/forums/showthread.php?s=&threadid=1291079

[Husky_1]

Thanks Randy, I will give it a look. BTW, have 400-600gph right now.

[Randy Holmes-Farley]

:thumbsup:

Good luck. :)

[betat]

I have been having a similar issue with my pump since starting to dose 2-part. I think that the calcium that precipitates out coats the impeller and when you stop the pump it locks up. I have had to remove the pump and "sand" the impeller down with a toothbrush to remove as much of the calcium as possible. Then the pump starts right back up.

Not sure what to do to minimize the precipitate. I have my calcium levels up over 450 and I only dose around 35cc per day for my 70 gal tank. I separate the doses with Ca added in the morning and alk added in the evening. When I add the alk it still turns the water in the sump milky white. Any suggestions Randy?

[ezcompany]

im guessing low magnesium is causing the residue build up. though i cannot scientifically explain this....whats your mg levels?

[Randy Holmes-Farley]

Next time you might try soaking the impeller in acid (vinegar or diluted muriatic acid) as it easily dissolves calcium carbonate deposits. :)

Yes, low magnesium can contribute to the precipitation of calcium carbonate for reason detailed in these articles. High pH is also especially important, as can be high alkalinity or high calcium.

A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium and pH
http://reefkeeping.com/issues/2006-06/rhf/index.php

What is that Precipitate in My Reef Aquarium?
http://reefkeeping.com/issues/2005-07/rhf/index.htm

[Husky_1]

Yeah, I mentioned this in the other thread that its my Alk portion that seems to be causing this. My Mag levels are still in inline at about 1325, this is down from about 1475-1500 1.5 months ago. I like to keep it high, but only measure occassionaly.

I am wondering if I am at a saturation point based on your article. My readings are test results much balanced, and my PH usually runs about 8.1. After reading the article, the precipitation make sense as well because the PH will be higher, especially in this area, so I cannot saturate the water as much.

I think I am going to dilute part 2 and see what happens, probably adding about 25% more water. After reading the article more in depth this time, I think that little precipitation is not an issue, as long as my PH is inline.

[Randy Holmes-Farley]

How can you know what part is causing it? The transient cloudiness on adding the alkalinity part is not indicative of permanent deposits forming. That magnesium hydroxide cloudiness is normal and not a problem.

[Husky_1]

Hey Randy, I guess I cannot say for sure exactly what part is causing it. I am 99.9% sure I am not seeing cloudiness. I am seeing a small amount of buildup around the outlet of the tubing. Not 100% because I am not there to scrape it off :)

The cloudiness I am use to, and have no issues with. If I were home right now I would take a picture to show you, I will try tonight.