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shellsea
02/12/2013, 02:34 PM
I have a 3 month old 120 gal mixed reef. Mildly successful. All rock and livestock relocated from a 5 year old 65 gal. Test results from a few days ago were:

11:30 AM 78.4 S.G 1.025 PH 7.7 Alk 8.6 CA 420 Mag 1420
Backed off on Mag and Calcium for now but when I dose Alk at about 9PM just as lights are going off. When it drips into the display tank it really "flakes up" like a snow storm. Clears up by morning.
Am I doing anything wrong? Normal?
Jack
Destin, Fl.

disc1
02/12/2013, 02:47 PM
What alkalinity supplement are you using? It is common to see a little snow as magnesium precipitates a little of the alk but that usually clears pretty fast.

MrClam
02/12/2013, 02:56 PM
Are you dosing in a high flow area? Concentrated supplements can precipitate if they are in a stagnant area because they dont mix fast enough.

shellsea
02/12/2013, 04:25 PM
I am useing BRS 2 part and yes it is in high flow area.

nynick
02/12/2013, 05:08 PM
Could be that your water is saturated already, if so it will fall out as "snow".

The part that I am not 100% sure about is if calcium can and alkalinity can percipitate eachother out. As in if your calcium is 110% of the waters max holding capabilities and alkalinity is 90%, will alkalinity percipitate out due to the high calcium? Or, do they both have their individual 100% max capacity.

Seems I can not raise alk when dosing Kalk so...got me wondering.

...Randy, yooohoooo.... :)

Josh_84
02/12/2013, 05:44 PM
I had the same problem with best 2 part. Started using baking soda instead for my all supplement and am much happier. It does not precipitate at all.

disc1
02/12/2013, 06:46 PM
Could be that your water is saturated already, if so it will fall out as "snow".

The part that I am not 100% sure about is if calcium can and alkalinity can percipitate eachother out. As in if your calcium is 110% of the waters max holding capabilities and alkalinity is 90%, will alkalinity percipitate out due to the high calcium? Or, do they both have their individual 100% max capacity.

Seems I can not raise alk when dosing Kalk so...got me wondering.

...Randy, yooohoooo.... :)

Sort of, but not exactly. There's a number called the solubility product. If you multiply the alkalinity times the calcium then it can't go over that number. Don't have the number off the top of my head. But if you try to go over that, then some will get together and precipitate until you are back below it.

Magnesium in the water helps to prevent calcium carbonate crystals from forming. So in reality, seawater is already slightly supersaturated with calcium and alkalinity.

bertoni
02/12/2013, 10:11 PM
I suspect you're just seeing magnesium hydroxide, as was mentioned. If you want to test that, you could test that by capturing some of the snowy water and seeing whether it redissolves rapidly in a container of saltwater. I'm not sure that it's worth the effort, but it might be easy to do.

shellsea
02/13/2013, 07:54 AM
Thank you David, Jonathan and others. Got new test kit yesterday and all new results. I am stopping all doseing for a couple of days and will regroup. Thanks again.

bertoni
02/13/2013, 08:39 PM
Okay, good luck!