# Magnesium Hydroxide (Liquid)



## ozfish (Feb 9, 2009)

I am trying to increase hardness using CaCl and MHL (Mg(OH)2 liquid) --- does anybody see a problem with this...I use the MHL as my water source has very low pH (5.4) and rich in CO2. I like the MHL as it raises the pH to 8 and gives me Mg that the water lacks. The problem is the Ca -- which is almost non existant in the source water....so I add CaCl down stream of the MHL. Problem is I cant seem to get a Ca2+ reading greater than 30ppm...no matter how much CaCl I add...I am thinking that I may be precipitating the Ca out of the water...

Any feedback or thougths would be appreciated.


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## ray-the-pilot (May 14, 2008)

ozfish said:


> Any feedback or thougths would be appreciated.


It is hard to say exactly what is going on here but the level of Ca that is dissolved in alkaline water is highly dependent on the amount of CO2 that is dissolved in the water as well. My guess is that if you do not add CO2 you are precipitating out the Ca.

I think if you want to get to higher GH you are going to have to use CO2 or some other Mg salt that isn't so alkaline, which means a lower pH.

In general high GH water with high ph is unstable and will precipitate Ca over time or rapidly with boiling.


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## SueNH (Jan 17, 2005)

Wouldn't it be safer and easier to use Epsom salts and calcium carbonate in some form instead?


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## Zapins (Jul 28, 2004)

Your tests might be inaccurate.


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