Hi planted tankers,
My plants are turning brown and I haven't been able to figure out why. Any thoughts would be appreciated! I'm talking about Java ferns, dwarf sagittaria, and hygrophila here (this is everything that's in the tank).
I've had the tank for several years, and the plants always grew well enough, but I've always had big BBA issues. 6months ago I turned up the CO2 more, as well as doing a one-off overdose of excel. The excel did a great job of killing the algae, and for a while I had a beautiful, algae free, healthy looking planted tank). but perhaps after 2 weeks or so the plants began to die off. Was a slow process that spread throughout the tank over several months, but now every corner of the tank has plants with brown, mushy leaves. The sagittaria do put out new leaves, but they don't put out runners. And many of the leaves are stilll brown. The Java ferns put out new leaves, but these invariably get brown blotches on them that spread to turn the whole leaf into mush. The hygro sometimes grow ok (mainly in the parts of the tank with less water flow), but many plants eventually get the same 'turn to mush' problem on their stems, old leaves, and new leaves. The BBA is back with a vengeance.
I initially thought I'd overdone it on the excel, but the fact that the problem has persisted for so long, and that new plants get mushy too, makes me think it's something else. Like turning up the CO2 has made the plants grow faster and exposed a deficiency somewhere.
CO2 is high enough, I think - kh/ph charts suggest it's well above 30ppm, and fish begin to breathe heavily when I put it any higher.
I dose KNO3, KH2PO4, and trace elements according to the guidelines here
So think these nutrients are ok. Although I'm not sure about my trace element mix - bought from a hydroponics shop, called 'aquatic chelated trace elements mix', and label says 'Contains all trace elements: Iron, Manganese, Boron, Copper, Zinc, Molbdenum,'..I've always assumed this would be sufficient for the trace elements part of EI dosing, but perhaps not...
Other parameters - KH is zero out of the tap, but I add baking soda to keep it at 2. GH is also zero, and I don't do anything about this.
I recently doubled my doses of all nutrients, in case for some reason the EI doses weren't high enough. However, I fgured that if this was the problem, upping the doses still would not help my mushy plants for some time. so, I bought some new Java ferns, put them in the tank, and hoped that they would grow beautifully and be mush free forever. No such luck! within 4 days of putting them in the tank they have started turning to mush too.
So, I'm now at a bit of a loss about what to do next. My thoughts are that either one of two things has happened:
1. Plants have caught a mush-causing disease, which is contagious. This causes my old plants to go brown regardless of anything else I do, and spreads quickly to new plants. But does this kind of thing ever happen?
2. Upping my CO2 has made my plants try to go faster and exposed some nutrient deficiency. Maybe the trace elements mix isn't good enough? Or maybe I need to do something about low KH/low GH?
And a related question - given that I'm still growing BBA like crazy, do I need to put my CO2 up even higher? (I've heard that BBA is a sign of insufficient CO2, but perhaps it takes high CO2 *and* healthy plants to get rid of BBA).
Thanks for reading right through this looong post! Any thoughts would be greatly appreciated. I'm at a loss here.