The Barr approach and Red Brush Algae...

Hi all,

I was wondering if I could please have some advise...

I have recently started NPK fertilizing following what I understood from the
Barr approach... I use PMDD made from the receipe on the Krib, but with the
australian equivilent trace element mix and I dose NPK based on what the
tank would need according to the Barr method... To the PMDD recipe, I also
add 2x250mg calcium tabs as my water does not have enough and my Rotala
Macranda dies off without it.

I started the Barr method two weeks ago and my tank is blooming with
red-brush algae on all the dying leaves and some not so dying leaves...

I read up on red-brush algae on the Krib and I couldn't find a definitive
answer... One article says that something is missing, one says that I have
too much of something... I have done all my tests and found the nitrate is
up to 10ppm (probably because of my discus feeding regime as they are young)
phosphate is .1ppm and Fe is non existant, which I am hoping is the
problem...

To start with, dosing PMDD at 1.5ml in my 50gal aquarium had a steady ramp
up of Fe to .04ppm, which my tank flourished at ( this was prior to the Barr
method, as I was still chasing down Potassium Nitrate and Phosphate), my
amazon sword flowered and everything was going great, then I noticed some
green spot algae on the sword, which I had previously discovered was a lack
of Phosphate.

I did the 50% water change and dosed NPK as per the Barr method, a week
later another 50% water change and then again with the NPK, then it
happened, it was almost over-night that the red-brush algae appeared, on the
hair grass, the sword, aponogeton and the rotala walluchi.

I am still dosing PMDD at 1.5ml a day and my Fe is remaining at 0.0ppm, but
i think i can attribute this to my amazon sword babies... there are about
20 of them on one flower stem that have roots which I think are sucking all
the Fe out of the water...? does this sound right? I read at greg watson
that if you dosed flourish at 1 tablespoon then you should does PMDD at 1.25
tablespoons, which appears to be in contradiction to the Krib, which says up
to 1/6ml per day for each 10 gallons... So if I followed the krib, I would
does at 5/6ml per day or greg watson would be 6.25mls every other day as I
was dosing flourish at 5ml every second day...

I have added some Fe seperately just to get my Fe levels up, but I'm
starting to think that this was not a good idea as the dosing of PMDD is
designed to bring everything into equilibrium and I have just ruined it by
adding Fe seperately.

Can someone please offer some advise with my problem?

thanks in advance.

Justin.

Tank specs:
200 litre (50 gallon)
MH lighting on 10hrs a day (was on 11 hours but dropped back when algae
appeared)
CO2 pressurized on PH controller 30ppm
KH 4
GH 1
Nitrate currently 10ppm but is usuall 5ppm
Phosphate 0.1ppm
Fe currently .2ppm after manually adding some.