Quartermain
10-23-2007, 9:20 PM
Some of you have been following my "Retrofitting a 125 gallon aquarium" thread. I have just setup a new 125 gallon aquarium and in it I used cement to build terraces into the hard scape.
The tank was planted over the weekend and I began regularly testing the water parameters yesterday. To my astonishment I measured GH at 380 (or 21 dGH). In a panic I performed several water changes and brought it down to 180 (or 10.08 dGH). My tap water is 80 (or 4.48 dGH) so it was quite easy to dilute the concentration. The level appears to be unchanged today.
This happened because, like an idiot, I was not testing GH regularly when the cement pieces were curing. Portland cement is, of course, mostly calcium. And calcium is directly linked to General Hardness. Clearly I have underestimated the cement's ability to leach calcium into the water column.
Finally coming to grips with my.... ignorance..... I tested the Calcium level. It was 80ppm. This was after the water changes. By comparison the calcium level in my tap water is not detectable with the Hagen test kit, so there's no question where this calcium came from.
Needless to say I'll continue to perform frequent water changes until they are no longer needed.
I have read that high GH is linked to poor health in both plants and fish. But these articles were talking about the cocktail of *all* dissolved salts, or what we refer to as Total Hardness. I can only assume that in my case Magnesium levels, for example, are totally normal. It is only Calcium that is elevated here. So strictly speaking we're not talking about GH. Just wanted to make that clear.
So my question is, was this really a chemical crisis?
Just what is the effect of high Calcium concentration on plants and fish?
The tank was planted over the weekend and I began regularly testing the water parameters yesterday. To my astonishment I measured GH at 380 (or 21 dGH). In a panic I performed several water changes and brought it down to 180 (or 10.08 dGH). My tap water is 80 (or 4.48 dGH) so it was quite easy to dilute the concentration. The level appears to be unchanged today.
This happened because, like an idiot, I was not testing GH regularly when the cement pieces were curing. Portland cement is, of course, mostly calcium. And calcium is directly linked to General Hardness. Clearly I have underestimated the cement's ability to leach calcium into the water column.
Finally coming to grips with my.... ignorance..... I tested the Calcium level. It was 80ppm. This was after the water changes. By comparison the calcium level in my tap water is not detectable with the Hagen test kit, so there's no question where this calcium came from.
Needless to say I'll continue to perform frequent water changes until they are no longer needed.
I have read that high GH is linked to poor health in both plants and fish. But these articles were talking about the cocktail of *all* dissolved salts, or what we refer to as Total Hardness. I can only assume that in my case Magnesium levels, for example, are totally normal. It is only Calcium that is elevated here. So strictly speaking we're not talking about GH. Just wanted to make that clear.
So my question is, was this really a chemical crisis?
Just what is the effect of high Calcium concentration on plants and fish?