I have an RO water / pH question - I'm watering w/ "distilled" water from
the dehumidifier that keeps the rest of the house safe from the humidity
that leaks out from my loosely enclosed table. I've noticed some root tip
burn and some chlorosis (I'm sure that's spelled wrong - lack of green in
new leaves) which I know can be caused by a multitude of issues from too
much light to not enough iron but I thot it might be pH related so I went
out and bought an aquariam pH test kit. The water before fert reads just
about neutral (7). after adding fert, pro-tekit, superthrive it's a bit
basic, maybe 7.2 or 7.3 which I don't think should be an issue... but could
something else be going on in the pot? How / should / could I check it?
The other interesting thing is that the dissolved salts in the "distilled"
water reads more than the water straight out of the tap - 40 ppm vs 33 ppm
here in Seattle.

"Ray @ First Rays Orchids" wrote in message
...
In addition to the great suggestions already mentioned, I'd suggest
modifying the feeding/watering regimen a bit: using straight RO water can
lead to really extreme pH levels, which can affect the availability of
nutrients to the plants.

Personally, I feed a weak solution of known TDS and pH at every watering.

--

Ray Barkalow First Rays Orchids
http://www.firstrays.com
Secure Online Ordering & Lots of Free Info!


"Jbkkhawk" wrote in message
...
Hello all, again. My Paphs--sukhakulii, gratrixianum, Magic Lantern,
and
a few
others just don't seem to be doing well. The leaves, especially the
older
ones, are pale, yellowish and waxy, and they don't seem to be growing
at
all.
My growing conditions: in my bedroom, days 65-70F, nights 52-55F, about
30-40%
relative humidity, some ambient light and about 12-15inches under 4ft.
flourescent lights. I try to keep them moist and feed with weak paph
fertilizer supplemented with calcium and magnesium. I use RO water the
rest of
the time. Is it just too cold for them or what? Too much light? I do
have a
mini phal that is in spike, but has sort of reddish tinge to the outer
edges of
the leaves and is not a strong looking plant...Thanks for any feedback.
Other
genera are doing okay. Cattleya skinneri is in full bloom!
Karl