Backyard Aquaponics
A place to discuss aquaponics

Good morning, I've attached some photos of the leaves of my strawberries. Can anyone tell me what the problem is? PH of 8

May I ask how you are raising your berries?

Anyway you can lower your pH? A high pH will lock out nutrients. How is your humidy? That may spread leaf problems.

Here is a link that might help with diagnosing berry problems:

http://www.fruit.cornell.edu/berrytool/ ... Rparts.htm

Thanks for the reply Bob, we got the strawberries as an after thought and stuck them in the flow tubes along with the lettuce. Sorry I should explain, my lettuce seedlings are dragging their feet due to the heat so we stocked up on some starter plants from the hydroponic center in the local Agricultural university. They had a lot of strawberries in flow tubes so we thought why not give it a go. Actually the few plants we put in dutch buckets are faring a little better, but like you said I think nutrients are being locked out by the high PH. The lettuce leaves are going yellow losing all their gren ect.ect. I'm going to check out the link you gave me and see what I can do about the high PH once again thanks for your help.

Hello Bob' just checked that link and found out exactly what the problem is...high PH/nutrient lockout

Well, this forum is priceless.
The info on about everything is phenomenal.
Visited that link and feel quite confident to not only add Boron/Borax, my future fish won't die, but I can even dip my finger it as well to get rid of all sorts of litte pains.
Phenomenal..........will start with minue amounts though, one never knows

Strawberries will do better with a pH in the 6's... but I've seen them doing okay in systems with high pH

From the photo's it looks like a Potassium deficiency to me, how old is the system?... are you adding Seasol or similar?... Potassium won't be locked out at pH 8.0... Iron is about the only nutrient that would be... and it doesn't look like Iron deficiency.

Also, have you salted the system?

No I haven't salted my system, what exactly do you mean by that?

Not sure where you found that in the link Gran...

Boron, and particularly Borax... has known toxicities.. especially for Rainbow trout fry....

http://www.esd.ornl.gov/programs/ecoris ... 520ata.pdf

http://www.env.gov.bc.ca/wat/wq/BCguide ... /boron.pdf


Granted when we stock our "fingerlings"... they're beyond "fry" stage...

But even with more adult fish I'D still be concerned...



http://www.greenfacts.org/en/boron/boron-1.htm

Strawberries don't like salt, so if you salt the system because of a health issue with the fish anything over 3 parts per thousand will hammer the strawberry plants.

1ppt salt, which many people run as a matter of course in their AP systems, is okay.

P.S. Other trace elements such as Boron, Zinc, and Copper could also start to become deficient above a pH of 8.0... but I don't think they are your problem, as I said before, the necrotic patches and margins as well as yellowing lead me to believe it's Potassium, not from high pH, just not enough in the system.

Most fruiting/flowering/seeding plants benefit from a Potassium boost... and suffer when deficient...

thanks for your interest Mr Damge, if the potassium deficiency is not from high ph then what is it? I'm getting a consistent reading of 5 ppm for nitrates, the Tomatoes are thriving even the celery seems to be doing OK. any ideas on how to lower my PH?
Thank you too Rupert, how can I give my system a potassium boost (naturally)

The Potassium deficiency could well be as a result of pH lock out....

With a pH in the range of 6.0-6.6.... most trace element are available... and boosting things like Potassium (if short)... can easily be addressed when buffering the pH of the system itself... ie Potassium BiCarbonate...

With your "high" pH... obviously you don't want to address the issue from a "buffering" perspective... so perhaps a foliar spray/feed.. would be the most appropriate method...

Maxicrop/Seasol... aren't particularly high in Potassium... but if it's more lockout related.. then a foliar feed with either of those two products might well solve the problem... and regardless will provide other trace elements anyway...

Try treating any top-up water with Hydrochloric acid to a pH in the low 6's a day before adding it to the main system. This way you won't be adding any further carbonates to the main system, so the natural acids produced by the nitrification process will be able to consume what carbonates are already in the system sooner, then the system pH will begin to drop by itself.

Top-ups should be done regularly so only small amounts are added, but if adding a substantial amount of acid treated top-up water, it should be done in stages, over a few hours.

How would a pH of 8.0 be locking out Potassium Rupe?... Potassium is locked out by low pH, about 5.5 or lower.

Actually you're right... my bad... was looking at Boron instead of Potassium...

I'd still go with the suggested foliar feed of Seasol or Maxicrop.

I'd also check the pH of the top up water the day after treating it and before adding to the system.