Using RO water with no calcium added

nekbet(6)September 12, 2013

So, after this thread I was helped to realize I was running way too high of EC for lettuce... and had some out of balance nutrients. I was using tap water with 200-250ppm and then adding nutes up to 1100 or so. oops.

So I switched out the main res with a lower nutrient solution using tap water...

And, I did a few lettuce plants with *just* RO water and general hydroponics nutrients, up to 600-700ppm. WIth no calcium or magnesium..

The image attached is a sample of what those turned out... not good... good experiment - now I know what calcium deficiency looks like.

The tip burn was much clearer an indication... the other thread picture was nutrient overload - browning/dying of the new growth, versus this was burning of the tips of old growth even.

Hope it helps someone to identify their problem later...

Thank you for reporting this comment. Undo
PupillaCharites(FL 9a)

Nice to chalk it up as an experiment ;-).

The worst conditions (which lead to tip-burn) are set up when too much nitrogen is applied as small plants causing an accelerated growth without a chance to transport sufficient calcium to the tender rampant growth, even when it is in concentrations that would be acceptable. Cutting off the calcium after overfertilization is like a lab experiment.

Part two of this experiement might be to do it over again (!!) with [35 ppm] to [100 ppm] of *soluble* silica (SiO2, molar mass = 60) in the nutrient solution from potassium silicate to see whether it added any protection (or made things worse).

    Bookmark   October 17, 2013 at 4:43PM
Sign Up to comment
More Discussions
PVC Tower System - Adding oxygen mid-stream
I have built my first hydro system from 4" PVC...
topher_cohen
Non-profit sustainable farm needs help to re-plumb hydro-system
We had two old hydroponics grow tables both about 4x4...
brettkp808
What can I do to learn more about planting or farming????
Hi all! I'm a beginner at hydroponics gardening......
skttls
Kratky Method Lettuce
I have been growing lettuce indoors using the Kratky...
nuverde
Started the hydro garden
I watched Bobby grow long enough and got busy. I bought...
radrob
© 2015 Houzz Inc. Houzz® The new way to design your home™