Backyard Aquaponics
A place to discuss aquaponics

Okay guys haven't posted on here in a long while. Have nursed all my ailing fish back to health from ich. Had a successful winter crop, now planted for the spring. Noticing some nutrient deficiencies in the plants. I've attached some pics for your expert opinions, as I'm still no good at diagnosing. I've added seaweed extract with iron 5 days ago with no improvement. Any ideas?

The plants are cucumber, cantaloupe, and squash, btw.

Hm. I found this page with pictures of cucurbit leaf disorders, and that looks more like one of the leaf spot fungi than a deficiency to me?

http://aggie-horticulture.tamu.edu/vege ... disorders/

Or could be sap sucker bugs?

Have a look under the leaves.

If you rule out the insects as mentioned above, then look into possibly adding some potassium. Potassium deficiency shows up on older leaves and is identified by tip burn on the leaves since it's a very mobile nutrient. All three of those plant types (melon, cucumber and squash) require decent amount of potassium to grow well and produce fruit.

What did you do to save your fish from ich?

For the ich, I actually followed colum black-byron's advice! I added salt to 3 ppt in my system because I had over 100 fish fingerlings and no hospital tank. It was cold out, but the salt did the trick after about a week and a half. It was not an instant fix, but I stopped losing fish pretty quickly and they were all totally better after 2 weeks.

So I looked under the leaves. There are a few microscopic brown bug things. Not enough to to do that kind of damage I wouldn't think, but who knows. The bugs are not on all the affected plants, however. This combined with the low number of bugs and their tiny size makes me think I should look for another culprit.

The salt, maybe? http://www.seminis-us.com/resources/disease-guides/cucurbit/salt-injury/

The edges on the lower leaves in the last photo could either be salt burn or Potassium deficiency. The spotting on the leaves could be from rain standing on the leaves and allowing either bacterial or fungal attack. I'd probably spray with seaweed like seasol or maxicrop. I don't think I'd be too concerned about the spotting at this point, I doubt it will spread much more (just make sure the leaves are dry before the sun goes down).

Might want to take a close look at those little bugs, especially if the temps are getting up into the 80's. They could be spider mites. Spider mites can an do cause stippling on leaves and could be the cause of the spotting. I think it's more likely bacterial or fungal but check anyway.

There's a picture of stippling caused by spider mites on this site.
http://www.clemson.edu/extension/hgic/pests/plant_pests/veg_fruit/hgic2207.html

Yep, pretty sure I have spider mites. Not an infestation, but like 3 or 4 on each leaf. I squished them by hand. Anything I can do to ward them off/kill them if numbers increase?

I've dealt with them on orchids and bean plants and neither of my solutions for them would work in this situation. (I used horticultural oil on the orchids and just pulled the bean plants when the mites got too bad). We'll see if someone chimes in with a solution that you think is acceptable. In the meantime you should do a search and see what you can find here on the site.

Here's one possibility, I've never tried this but looking online I found a recipe that uses milk and flour dissolved in water.
1 Tablespoon Milk
1 Tablespoon Flour
24 oz water
Combine and shake well.
The idea is that the spray coats the mites and their eggs and smothers them. It has to hit them to work so you have to spray well everywhere on the plant. Since this is how the horticultural oil spray works this should work as well. This might also work on scale and mealy bugs. I think it should be safe for the fish since the system water will just make it less sticky (but as mentioned I haven't tried it, might not even work on the mites ). After a couple of hours they spray it off of the plant - it sounds like doing this late in the day might be best since it could cover the stomates and cause the leaves to overheat.

Cheers