From: Robert Brunner <brunner at aecom_yu.edu>

> I recently bought liquid chelated iron at a gardening store. Its called 
> GREENOL. It is 3.64% Sulfur, .13% chelated copper and 6.13% chelated 
> iron. (Also .10% chelated Zinc). Has anyone heard of this. I am not sure 
> of the dosage to add to my tank. I have a 150 gln discus tank and do 
> water changes every 3 days.

Since it is 6% chelated Fe, then you would use it in the same
proportion that you would use PMDD. For example in 600ml (roughly
two cups) of distilled water, add 1 tbsp. If you have high
nitrates or ammonia in your water, skip the potassium nitrate
in PMDD but don't forget the potassium sulfate & magnesium sulfate
(epsom salts). If you have soft water, you should add CaCO3 or
CaCl for calcium. I use 1 tsp CaCO3 (technical grade from the
drug store 6$/500g) for each 10 gals of water I change. The
greenol may lack boron, molybdenum and manganese micro-nutrients.
I think Paul described how to use borax for boron previously.
Soil or subsoil from your back yard probably contains plenty of
all three micro-nutrients and so if you used soil in your substrate
(mixed with sand and clay) you'd probably be fine.

I believe there was an article in TAG a couple years ago about
the use of greenol. Was it Vinny Kutty? "The Quest" 
(TAG 6:6,7:1,7-2) or Thomas E. Marquis "HERE'S MUD IN YOUR TANK"
(TAG 4:6,5-1) There's also a lot of articles by Paul Krombholz
in there about green water control including The Daphnia Cage.

Kevin or someone: could you post _here_ a revised formula for PMDD 
which has the adjustments for increased potassium (K) ?

Someone else posted about green water treatments but I can't find
the posting. You can use a micron filter with diatomaceous earth
to remove the unicellular algae. A good quality filter will
saturate with algae in a day or two so there's no concern about
using one continuously. Once you've eliminated the outbreak and
control your levels of phosphate and iron, you shouldn't have
a reoccurrence (unless you've got too fertile a substrate ;-)
I think its important to fertilize K per Conlin/Sears method
and probably supplement Ca & Mg as well with fertile substrates
until you've got the nutrients & plants in balance.

Another way to treat green water is to grow a heavy cover of
floating plants like Salvinia. That will play havoc with anything
else growing in the tank however so I don't recommend it at all.

Oh, yeah. A defective or old micron filter may not be very
effective at filtering out the green algae. If it runs and runs
and never gets plugged and the water stays green, this could
be the problem. I have two old and one new filter like this. <:-\