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

Hydroponics fertilizer



I've just started to use a product by Manutec as a sort of premixed PMDD. 
It's a two part fertilizer and costs 500g for $5.75 (c.US$2.50) so the 
price is right. The details are
Packet 1
N as nitrate 6.2%
N as Ammonium 1.4%
Total N 7.6%
P water soluble 3.1%
K as nitrate 18.2%
S as sulphates 3.5%
Mg as sulphate 3.5%
Fe as chelate 0.34%
Mn as sulphate 0.08%
Zn as sulphate 0.04%
Cu as sulphate 0.03%
B as sodium borate 0.003%
Mo as molybdate 0.001%
and Packet 2
Ca as nitrate 19%
N as nitrate 15.5%

And when mixed as directed you should get
N-215ppm
P-37ppm
K-218ppm
Ca-152ppm
S-54ppm
Mg-42ppm
Fe-4.08ppm
Mn-0.96ppm
Zn-0.48ppm
Cu-0.36ppm
B-0.036ppm
Mo-0.012ppm

I've mixed it half strength and have been adding 5 drops per US gallon per 
day for the last three days with no obvious ill affects re plants, fish or 
algae. I've only got 1.5 wpg and brewing CO2 so I don't think I need to 
boost things up too much. Filtration is just an internal power head with 
sponges. There are only four small blue-eyes as fish in the tank and 
salvina & duckweed to take up excess water column nutrients.

It all seemed fine but I've been reading the warnings about adding ammonium 
to tanks and now I'm concerned. I think the ammonium works out to be about 
8% of the total N in the prepared mix. Any thoughts or comments or "OMG 
stop using that poison!" statements?
Cheers Tony