Problems with getting plants growing

[Devoid]

I am in central Texas and built a raft system based on Friendly Aquaponics instructions.

Water temperature is up to 92

ph 7.7

ammonia 0.5

nitrate 10

nitrite barely above 0

Seed starting bed

Plant Problems

Tomatoes originally looked like Iron deficiency and I added iron, then it just started getting light green all over

Pumpkins that are now completely dead

Cucumber with same type issues and it's roots

Okra - left 3 are a week or two older then the ones on right

So any thoughts or ideas on what to do to get this going? I'm looking for a good low cost d.o. meter. I'm also wondering if putting them out in full sun in just frying them.

[Gena]

Devoid , below is the URL to a good article on iron deficiency that I received in my email today. Maybe you got it too. I'm on every Aquaponics newsletter out there. LOL

http://theaquaponicsource.com/iron-in-aquaponics/

[Devoid]

Thanks Gena. I think the little checkers are neat looking. Not sure how often they need to be calibrated which has been one of my questions. Not a lot of info as they're new.

I'm looking to add two more grow beds and I need to figure out how to put a greenhouse for the winter months as cheaply as possible.

I'll be growing lots of lettuce but would like to keep a few tomatoes and all fruiting if possible.

[Gena]

Devoid you might want to take a look at the following youtube presentations. This guy gives a lot of good info on iron. Many things I've read say that people routinely add iron about every 3 wks because it is usually the nutrient that is lacking the most. I think the iron checker is a nice little gadget , if it works, but too pricey. If you add the iron following the equation in the 2nd video, I would think you will be fine without it.  Do keep trying to get your pH down and if you add iron make sure it's the proper one for your pH. Your plants just may be having trouble taking up the nutrients with such a high pH. I started some lettuce from seed and will putting it in our rafts this weekend hopefully. I hope my water isn't too warm for it. 

http://www.youtube.com/watch?v=E4_hCAnymFw

http://www.youtube.com/watch?v=qczagOJG5mI

[Devoid]

Yeah I'm not sure how the temp will effect the lettuce. I'm going to plant a couple each week so I get perpetual harvest for personal use.

I couldn't find a powder chelated iron and currently have a small get bottle of liquid. Do you know where I could get it in college station? I didn't think to ask at producers when I was there.

Duo you have relishing on your troughs? If so how are they made?

[Gena]

I got my iron from ebay. I do a lot of shopping there for mesh cups, rock wool, etc. The iron I got was Sequestrene 300 FE 10%. It was one of the ones recommended in those Youtube videos. 5 lb. was 49.00 including shipping but it should last for years. I'm not sure what you are asking about the troughs. Our growbeds are 4 x 8 ft. with pond liner. We have put a few river rocks on the bottom for more surface area to capture bacteria. I'm sending a pic. It's a U shaped setup with 3 tanks and growbeds. Ea. tank is 300 gal. 

[Devoid]

Nice clean setup you have there.

I'm just trying to figure out best way to shade cloth and trellis my plans.

I also seem to have gnats all over the plants now. Little bugs that only fly a short distance.

[Devoid]

Turns out the iron I have is iron edta best that I can tell. So I'll try a foliar feed as I think my basil is iron deficient but could easily be wrong

[Gena]

Devoid, I'm thinking this is not an exact science. We could easily be wrong about a lot of things. We actually have beams going across the top of our greenhouse structure for wind support. They will also serve as a support for strings to hold up our plants when they get big enough. Have you thought about building something like a pergola over your growbeds? That way you could run some 2 x 4s across the top and maybe attach your lattice that way and also you could spread some 50/50 shade cloth across the top. Of course you would  have to sink some corner posts to do it. But it's not that difficult. My husband built one for our picnic table. BTW I think I remember something in the youtube video about NOT using EDTA. You need the Fe DPTA or the Fe EDDHA (if you have a pH higher than 7.5) Watch those videos on the iron. It's really good info. 

[Devoid]

I guess I'll have to look through the videos for that info. My to do list is just huge.

That sounds kind of what I was thinking for putting shade and trellising together.

I foliar fed them. At this point I can't regret it too much as they're not doing too well anyway.

[Alex Veidel]

That doesn't look like spidermite damage...My guess would be either what Gena said about nutrient lockout due to high pH, your little tilapia nibblin' on the roots, or maybe the sun is scorching your leaves. Some times that intensifies if your plants are getting water on the leaves, or if you've applied some kind of foliar insecticide (organic or non) and the sun hit it .

Devoid said:

Thanks Gena. I've been trying to figure out the best way to combine a  shade structure with a trellising structure. I'm also going to need to put some greenhouse over it all, so I'm considering using the shade/trellis structure to hold up some greenhouse plastic. That way won't need to keep as extra air warm.

It turns out that a small tilapia or tilapia egg ended up in the grow bed and was eating all the roots. It explains some of the damage, though I'm positive there are still spidermites and aphids.

[Alex Veidel]

Whoa, there's whole page to this conversation that I didn't see :)

I would recommend getting your pH down before adding too much iron. High pH does tend to lockout iron especially, so even if you are adding it, your plants won't take it up. There are certain forms of iron that plants can take up at higher pH levels (like DTPA) but your system will still need to be below 7.6 for it to be effective.

[Devoid]

I was told the ph should naturally fall with the fish added, but hasn't yet. I meant to check it again yesterday but forgot.

My basil leaves were turning yellow but veins were still green.

Still need to figure out the new bugs and treat them. Got a dust meiser in today to dust everything in diatomaceous earth