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

Iron, Copper, K2SO4, Chlorine, GH

Thank you James for such a thoughtful response.  Please bear in mind that I
find testing helpful, as I learn to develop my "plant-eye".  A brief
follow-up, if I may:

James Purchase Wrote:

"Caleb has some questions...."
""...Therefore, there may be a better (or additional) guide
for the OTHER trace nutrients.  One example may be to test/dose for Copper,
and keep it BELOW a certain level.  Does this make sense when dosing a trace

"That would depend entirely on which trace element mix you are using, and
much Copper there is in it - if you look at the component lists for 10
different trace element mixes, you will probably find 10 different sets of
numbers - they can vary quite a bit."

I use Chelated Trace Mix from Homegrown Hydroponics.  I believe it contains
the following: 7% Fe, 1.3% B, 2% Mn, 0.06% Mo, 0.4% Zn, 0.1% Cu, EDTA, DTPA.
Assuming these ratios are reasonable, my question becomes: what is a good
not-to-exceed level for Copper, and is copper the nutrient to use on a
not-to-exceed basis?  This would serve as a guide for me, until I develop my

""..."I also find I do not need any K2SO4
to keep Potassium at 20-30ppm.  If I add it, I get to 40ppm.  Is there any
reason to add K2SO4 if the KN03 seems to provide sufficient Potassium?  My
plant growth is fairly high, plants are quite green, and no algae (yea!).""

"In addition to Potassium, the K2SO4 is also a potential source of Sulfur,
another important macronutrient. But Sulfur is also in (MgSO4 + 7H2O). Also,
depending upon how much Sulfur is in your water supply naturally, and how
much is added via fish food, you may not need the K2SO4. Have you tried it
both ways - with and without the K2SO4 and looked at how your plants react
(as opposed to spending so much time with test kits?)..."

My plants have SEEMED to do better with both KNO3 AND K2SO4, even though my
Potassium level is extremely high.  Maybe I was low on Sulfur, or maybe it
was simply that my tank has come into overall "balance".  It is only 3
months old.  I suspect the latter and will keep Potassium to reasonable
limits (20-50 ppm).  I will also check with my water utility re: Sulfur.

"That would depend upon whether or not the water contains only chlorine or
it contains chloramine (chlorine+ammonia), and how much of either is

My water utility does use Chloramines.  My tap water tests with LaMotte kit
at: Free Available Chlorine =.2ppm, Total Residual = .8ppm, Combined = .6 (I
believe Combined is, infact,.6 not 1.0 which would intuitively sound
correct.  Again, my real question is, what level, greater than zero, is
tolerable during a topping-off, etc.  Also, if one does a water change
directly from tap to tank, does pre-treating the tank water for the quantity
of tap water to be added do the trick, or should one always treat the tap
water in a bucket first?

Thanks again!