high temps and low frequency watering can induce water stress. The plant relies on transpiration to transport water and nutrients internally from root to leaf. When a plant is under water stress, its ability to uptake nutrients is adversely affected (no water = no nutes) calcium deficiency is usually the first to appear, adding more calcium to the nutrient solution will only make things worse as its not a lack of calcium its a lack of water moving through the plant :)
A mature tomato plant will get through half to one gallon of water per day.

The flower drop on the peppers may be from a lack of pollination. I do a few DWC peppers in a greenhouse and I pollinate them with a small artist brush. Wait until the flower is fully open then lightly brush the inside of it. It works for me.

Thank you both!
We immediately changed over to 300 watt daylight CFLs 6500k. Temp is down to 78-81 degrees and humidity is 70 tops. Seedlings on the side are doing much better and tomatoes have improved and are taking up water again with some new coming on. The first one is still green but growing. The peppers look better and I will begin pollinating them-I was sure that they didn't need that but obviously they do!
Our future goal is a ventilation fan for further cooling.
So do you see a problem with the tomatoes and peppers sharing the same tank of water? This does not have to do with the two not getting along, right?
Thank you again!

The toms will need a slightly different feed to the peppers in the flowering/fruiting stage so it would be a compromise.
The CNS17 Bloom and Ripe look hellishly heavy in phosphorus and toms dont need all that much. The cns grow supplemented with a little potassium nitrate (KNO3) looks like it could fulfil all stages of growth depending on the micro-nutrient content (which i couldnt find values for).
The peppers should do fine with 6.5ml/L CNS Grow + 0.75g/L KNO3, (EC: 2.1). The toms use the same feed upto the 4th true leaf at which point they`d need 7.5ml/L CNS Grow + 0.993g/L KNO3 (EC: 2.5)
To make the KNO3 additions easier, put 4L of distilled water into a 5L container with a lid, add 500g of KNO3, wait for it to dissolve and topup to 5L with distilled water. The 0.75g/L becomes 7.5ml/L and the 0.993g becomes 9.93ml/L, but 10ml/L will be close enough.

Thanks!
Purchased the potassium nitrate tonight(in the form of spectracide stump remover granules).Plan to try your suggestion soon.
Now I was told or read somewhere that the CNS17 Grow was too high in nitrogen once the tomatoes started to flower and you must switch to a lower nitrogen formula at that time, or else no tomatoes. Is there any truth to that?
Also, should I still consider the cal mag supplement in addition to your regimen?

CNS17 guaranteed analysis
Total nitrogen 3.0%
.14% ammoniacal nitrogen
2.86% nitrate nitrogen
Available phosphorus P2O5 2.0%
Soluble potash K2O 4.0%
Ca 2.8%
Mg .5%
Sulfur 1.1%
Mn .05%
Mo .0005%

I am really desperate for some results although I know it will take time. Thanks again.

A lot of growers reduce the N in flower, i guess its carried over from soil growing where high levels of ammoniacal/ureic N caused soft lush growth and very little fruit.
Hydro nutrients have very little ammoniacal N and no ureic N. Most hydro growers that drastically reduce N in flowering also say its normal for the lower leaves to look sickly and die off when its indicative of the plant relocating N from the older leaves to make up for the missing N in the feed.

This post was edited by hex2006 on Mon, Jul 14, 14 at 0:29

OK, now that I've went to try that regimen, I found that I am confused about using the g of potassium nitrate. Following your "To make the KNO3 additions easier," which I assume is to be used at full strength, I would have to go through alot of potassium nitrate to get to 40 gallons. Also, do you know of other sources as this is $5.49 per 453 grams at Menards here and if the above is correct it would not be an option for us at that price, especially every two weeks.

What I was thinking from your suggestion of 0.75g/L KNO3:
40 gal x 2.2L/gal = 88L x0.75gKNO3/L = 66g KNO3 total, and
6.5ml/L grow x 2.2 L/gal =14.3 ml grow x 40gal = 572 ml x 1oz /30ml = 19.06 oz grow total

Now, I will admit that I had been only filling the tank to 30 gal and calculating for that to save on nutrients. Now I realize that may be part of the problem.
What are your thoughts? Am I really off here? I am not seeing any changes in my plants again so I would like to change to something like the above soon if I could do it long term financially. Thanks again!

Stump remover will be a lot more expensive per lb than horticultural potassium nitrate. I pay the equivalent of $0.77/lb for mine (Yara Krista K+) but its probably even cheaper in the states.

Haifa Multi-K, Greenhouse grade Potassium Nitrate seems to be a fairly common one in the US.

This post was edited by hex2006 on Fri, Jul 18, 14 at 3:46

The dutch buckets have had 66 g KNO3 and 19 oz Grow nutrients per 40 gal reservoir for 1 week today. Less "dying" of tomatoes, some growth returning, and flowers starting to grow tomatoes. The "2 month old tomato" is almost "ripe." They have went through about 5 gallons of water in this week.
The peppers, in the same system, have more flowers now, but I think they are continuing to drop despite pollination with a small artist brush, hoping this gets better this week.
PH was 6.3, ppm (I hope to get EC soon) was 1250. Today, one week later, pH is 6.2 and ppm is 1340(Not sure what I did there but I also have 2 little helpers to distract me often).
Temp is about 76, but did let get to 84 one day last week. Humidity is 65%.
Plan to add 1/2 strength nutrients of what I did last week plus water tomorrow night. Would you agree or is this not the right path?

With peppers and tomatoes in the same system the nutrient strength will need some compromise. I`d reduce it by 25% rather than 50%,PH to 6.0 and track the ppm. Dont forget that as you reduce the feed strength, the elements coming from the tapwater will increase proportionately, calcium being the main one.
You`ll likely find the starting PH will be higher with the weaker feed and the larger percentage of carbonates in the water vs nutes (which are somewhat acidic so higher EC = lower PH) will tend to buffer the ph up for a while so you may need to add more acid (ph down) at the start and a little more periodically to keep it in range.

This post was edited by hex2006 on Tue, Jul 29, 14 at 3:09

Yes, you were right about the pH being higher, but once I got it down it stayed and is 6.2 tonight. PPM is 1430 so I think I am starting to digest your info regarding the tapwater elements. Added water today, we are going through more now, but still slow. Plan to clean reservoir and start with new nutrients Aug. 3, same plan but at 1 week only reduce added nutrients by 25%.
I am considering starting 4 tomato seeds to replace the pepper plants until I get the tomatoes figured out. One reason being that I have what I think is an isolated thrip problem on 6 lettuce plants and 1 pepper leaf, treated once with neem oil and no bugs spotted since spraying July 28. Another reason being that peppers will not be as valuable to me this winter, much to the dismay of my spouse.

The peppers would take priority here as the wife loves her hot peppers. Another reason is they have more time invested, they get cut back and overwintered every year. Growing the hotter varieties from seed i`d have to start indoors in january for a decent harvest in november. Toms are lightning fast in comparison.
If your recovering tom plants have non flowering sideshoots of a decent length, i`d throw some in a glass of water to root. They will be ready to go into the system in a week or so..much quicker than starting from seed. You can use flowering sideshoots but ime they take twice as long to root.

I have two tomato plants that are actually dying now. I have saved some sideshoots which will be planted soon where I took out the peppers.

I have noticed a major change in our lettuce since switching to the CFLs. Although the temperature has stayed down, about 80, our lettuce had stunted due to lack of light, and the tomatoes are showing it too now. (Not to mention thrips on my lettuce, ugh). The plan is to purchase some LED grow light panels-full spectrum 400 watts.

My indoor garden is such a downer right now when everyone outdoors seems to be thriving!

Received our first full spectrum 400 watt LED grow light. Plan to test it for a week on lettuce then hopefully order 3 more to replace the CFLs.
Threw out a bunch of leaf lettuce infested with thrips. Neem oil was worthless against them. Found some thrips on the tomato plants and ordered Spinosad.
Whew! Only the basil has continued to do well in spite of all!

Any updates on this?

I have just started to use CNS17.. apparenty there are two formulas... one for Hydro Grow (3-2-4) and soil/coco grow (3-1-2)

Not sure which one is actually better for Hydro. How many ml of CNS 17 do you use per gallon? 10ml of it into a gallon usually sits at around 550ppm on my bluelab combo meter with a PH of about 6.2. I find this amount is perfect for starting small and midsize plants out.

SM-90 will knock down the thrips.

I have started some Tomatos in my system here that I will post about later.

This post was edited by agentpatience on Sun, Sep 21, 14 at 5:15

I doubt that either will respond as its been since 2014 on last post from either. Are you sure that you didn't get their problomatic system from them? Lol...

J/K

ID give it one more time at the nft then just say that kratky Is pain free and convert over. See you in 30 days.....ill help harvest and bring 5 gal buckets for ya