02-07-2005, 10:59 AM
Join Date: Oct 2004
Location: San Jose, CA
I would like to summarize my experience of treating calcium deficiency symptoms in my tank so far.
For almost two years, I simply could not grow Rotala macrandra, or its relative r. magenta. I get stunted, twisted/deformed new growth. The plants keep trying to send out new growth, but the vicious cycle continues. In severe cases, the new growth turned white and disintegrated. It never occurred to me that it might be Calcium problem because my tap water GH=8. But when I observed some other plants like Ammania gracilis displayingthe same twisted/deformed leaves, I decided to give Ca supplement a try. Couple of months into Ca addition(first using CaCO3, now CaCl2 bringing GH to 13), my rotala macrandra is unbelievably beautiful and weedy, completely blood red. R. magenta is doing much better as well. Ammania is somewhat better but still has twisted leaves(not stunted), perhaps I should further increase Ca dosing.
I don't believe it is absolute Ca deficiency in my case. Although I don't have a good test kit to accurately determine Ca:Mg ratio, I believe I have plenty of both in the water. Perhaps not high enough Ca:Mg ratio? Or even maybe Ca:TDS? It is not Ca:K in my case because I have varied K dosage without seeing a difference. My TDS is about 300, so K variation does not change TDS much.
An incident over a week ago sort of confirmed my belief of relative deficiency. I dosed Oxytretracycline in my tank to treat some fish. And the plants response was not what I expected. I see red plants like Rotala macrandra 'red' and 'green'(yes, even 'green' can be red too), r. wallichii, r. magenta, ammania gracilis, a. senegalensis, a. bonsai, etc. sending out HOT PINK/MAGENTA new growth, while green plants like stargrass, Eichornia diversifolia, pearlweed, rotala nanjenshan, rotala sp. 'green' sent out new growth totally WHITE. After a quick google search on Oxytretracycline, I realized it will react with Fe and other metals(Ca, trace, etc) in water so I am probably seeing a severe case of Fe/trace deficiency right now. However, the hot pink new growth on Ammania is totally smooth without Ca deficiency symptoms, probably due to the abundance of Ca after CaCl2 supplement. So Ca deficiency in my tank is indeed relative to other elements.
Another conclusion I draw from the above incident is, if I see hot pink/magenta color in red plants in other people's tanks, I know it is not due to Iron(more likely the lack of it), I get blood red, rusty red/orange new growth when Iron is abundant.
Last edited by shalu; 02-07-2005 at 11:28 AM..