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

Rising iron levels?

I am at a loss to explain the iron readings in my 29g. tank. Two weeks ago I
switched from using Flourish as my liquid fertilizer as I suspected it to be
the cause of the brown film on plant leaves and on the glass near the
Flourite gravel substrate, to Tetra's Florapride(just iron and Potassium). I
also added Hilena Crypto tablets (1-0-25) into the gravel near the roots in
the amount recommended by the manufacturer. From what I read on the APD, the
iron gluconate(in the Flourish) might precipitate out of solution and cause
a brown film. I have made a trace element mix (loosely based on PMDD)
composed of 1 tsp. magnesium sulphate, 1 capsule manganese citrate, 2
microspoonfuls( the measuring spoon in Tetra's nitrate test kit) of boric
acid in 167ml. of distilled water, dosed at 2 drops/29g. after weekly 1/4
partial water change.

The odd thing that I've noticed is that I used to add 1/8 tsp. Flourish
daily before, to achieve a reading of .1mg./L on my Hach iron test kit and
now after adding only .5 ml. of Florapride instead of the recommended amount
of 10 ml. with my weekly water change I'm getting an increasing iron reading
after 2 water changes without adding any additional fertilizer! The reading
has risen from .1mg./L one week ago to .2 mg./L today. Am I getting a false
reading from the other trace elements or could the Hach test kit not be
testing the new form of iron from the Florapride accurately?

By the way, the brown film has mostly disappeared at this time and in spite
of not adding any fertilizer for two weeks the new growth is still green.
I'm not complaining but still I'm flummoxed as to why the iron readings are
rising of their own accord.

Susan Romano