[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: green spot algae

I've always had green spot algae, to one extent or another in my tanks.
Recently, it started getting rather worse than usual.  I got out my
test kits and found that my nitrate levels were very high (>60ppm).

I didn't know whether the nitrate levels alone were causing the spot
algae to grow or perhaps an excess of phosphate (for which I have no
test-kit).  Other algaes were not growing.

Anyway, I have never had a positive iron reading, but I thought this
must be a problem with my (LaMotte) iron test kit, 'cause according to
my calculations and tests of the PMDD I created, it should have been
.1ppm.  So I tried adding more K2SO4, but that changed nothing, then
I tried more MgSO4, and that changed nothing as well.  Finally, I got
smart and started adding more trace elt. mix.  I noticed an immediate
increase in bubbling and lo, I finally got a ~.1 ppm reading on my
iron test kit.

After some weeks, the nitrate level decreased to <20ppm, and the
green spot algae decreased dramatically.  It's not completely
gone yet, but the stuff doesn't do much damage to sword plants
anymore, and only inconveniences my anubias and other slow-growers.

So, my advice is, if you've got lots of green spot, go out and get yourself
iron and nitrate test kits in anticipation of having to tweak your PMDD

					- Steve