Tom, seems I remember you saying there was an ideal GH of 3, a KH of 5. I know that plants can thrive within a wide variance, but is there an ideal GH and KH, and perhaps a Ph, that in general, is more beneficial for plant growth? :gw
aquabillpers said:High pH reduces the amount of CO2 that water can hold. Above 8.0 it greatly reduces the kinds of plants that can be maintained.
This is very significant in non-injected tanks.
aquabillpers said:So, to rephrase my question, if there was one glass on a table that contained water with a pH of 8.0 (and a GH of whatever), wouldn't it would contain relatively little CO2?
So I would surmise that only a small number of plants could be cultured at such a high pH, those few that could use the KH as a carbon source, such as vallisneria, sagittaria, elodea, and ceratophyllum. Right?
Thanks for the continuing turoring!
Tom Barr said:No, there are many many plants that use bicarb. Myrio's, Swords, Egeria, Hydrilla, all pondweeds, vals, sag's that's not a few..........
From the pH/KH table=>
pH 7 and a KH of 1=> 3ppm CO2
pH 8 and a KH of 10 => 3ppm of CO2
They have the same CO2 and both are at about ambient levels.
Which has more *total* carbon?
The one with the higher pH.........now why?
aquabillpers said:That's not a few, I agree, but as a percentage of all aquarium plants? Maybe 5% (to pick a number) can use bicarb directly AND thrive?
I think the consensus is that crypts in general, for example, cannot use bicarb. But I've also read postings from people who say that they have done this, so . . . ?
Yes, I see that, but if the carbon in the bicarb is not useable by the plants that one is trying to grow, of what use is it?
Maybe a better question is, "What plants cannot grow in a high pH/low CO2 environment, without special measures like very high levels of lighting and ferts?"
HelloRe: GH and KH
More likely I said a GH of 5 and KH of 3.
GH should always be higher than KH if you have a choice.
I think pH has little relative importance wereas total GH/KH and CO2 do.
-do you give me ask
-For GH=5, what is the ratio of Calcium and Magnesium?
HelloTalk about revival of an old thread!
I just had to answer a 13 year old thread.
What does your Ca test show?
Once known this equation can be used ((17.86 x dGH) - (2.5 x Ca ppm)) / 4.1 = Mg ppm
A standard ratio is Ca:Mg::3:1
HelloPretty close to 3:1
Originally you stated GH was 5???
I try to keep @ least 20ppm of Ca