adding elements to calciumhydroxide

[Tmmste]

I wondered which elements I can add to calciumhydroxide. E.g. brightwell uses kalk+2, containing also magnesiumhydroxide and strontiumhydroxide..

Would it be possible to also add e.g. potassiumhydroxide.. (not to the brightwell, but I would measure x amounts to add to my top-off reservoir) ? any other suggestions?

 

[Randy Holmes-Farley Verified Community Expert]

There's not much you normally dose that you can add.

Brightwell kalk+2 is not a useful product. There is hardly any magnesium in it (not nearly enough to be balanced) and the magnesium that is there won't dissolve at the pH of kalkwasser. It was apparently designed by a "marine biologist", not a chemist of any sort. lol

You cannot add hydroxide or calcium (they will suppress dissolution of calcium hydroxide) or magnesium (it will precipitate as magnesium hydroxide). You cannot added bicarbonate or carbonate (they will preciptiate calcium carbonate).

Sodium or potassium nitrate could be added.

 

[Tmmste]

Hi Randy, thank you for this explanation. Well, that leaves hardly anything to add, I prefer not to add anything bound to nitrate. I guess I will stick with plain old calciumhydroxide.