Newer leaves curling up, yellowing margins, burnt look?

The Classic 6 has a flap over the front/center of the tank, so I'm always adding nutes directly to the tank when I feed that one. I didn't realize it could cause problems if I did that in other gardens but I will definitely go back to adding nutes to the Sprout's front compartment and the Bounty's corner! I've been giving the Classic 6 the standard 3 mL of Mooch for tomatoes each week, but I was only giving 2 mL to the Sprout. Should I go down to 1 mL for the Sprout and 2 mL for the Classic?

I did some reading, and it seems that burn shouldn't cause the leaf issues you're having. It would turn the edges brown, but with downward curling not the upward curling. Indoor hydroponics are quite different than outside, soil growing problems, assuming when it's warm you have screens on your windows and don't bring in outside plants.

This was very helpful: homeguides.sfgate.com/hydroponics-leaf-curl-35277.html

"Specific Problems

Look closely at the leaves to help determine which nutrients is off balance. When the leaves are dark green and curled downward, it's likely you're overfeeding them and they are trying to process too many nutrients. Cut back on the solution for a few days to see if that eliminates the problem. When leaves curl upward, they are missing a vital nutrient. With a potassium deficiency, it's the older leaves that curl and begin to turn yellow. When the solution is lacking sufficient calcium, the younger leaves start to curl and become stiff. Younger leaves are also affected by a lack of boron or zinc. When the leaves on a plant take on a blue hue around the edge and curl upward, check copper levels, which are likely too low.

Corrective Action

When you first notice leaf curl, spray the affected plant's leaves with an all-purpose plant fertilizer. This provides emergency nutrients for the plant. Examine the plants to see if others are showing signs of leaf curl; it could be centralized to one species or it could be affecting all of the plants. Change the mixture of nutrients in your solution to help correct the problem, adding new solution each week. Make sure you pulverize any nutrient crystals before mixing them with water to create your nutrient solution; it's possible you have the right nutrients but that they aren't dissolving adequately. Measure the pH of the new solution, as the plants can't absorb the nutrients well if the solution becomes too acidic or alkaline. Stick to a pH of around 6.5 for the best results."

I hope this helps.


 

Thanks, everyone! Yes, I've been using distilled water only. I don't pre-mix nutrients, but I had started adding them through an unused hole instead of through the side, thinking they'd be more evenly distributed that way. A month ago, I bought a set of meters for pH and conductivity (?), but haven't used them yet since the pH meter needs to be calibrated. Maybe I'll do that tonight, in case a wonky pH is making the nutrients unavailable.

Yikes! The pH in the Sprout measured 3.87! The pH in the Classic 6 measured 4.44! I tested a cup of tap water to make sure I wasn't getting false lows and got 7.51. The Classic 6 is due for a R/R tomorrow, but the Sprout just got one on 2/13.

I had ordered a pH Control Kit (General Hydroponics) around the same time I had ordered the meters. I just opened it, and ironically enough, it has a vial and drops for testing pH, no calibration required! But I'll probably do a rinse/refill on both, anyway.

OMFG. I figured out what happened... This morning, I went by Winn-Dixie before work to pick up a few jugs of Steam-Distilled Water. They were completely out of distilled water, so after work, I stopped by Publix to pick up some Purified Water. I had assumed that this was their version of distilled water, since they don't sell anything labeled Distilled Water, but the jugs of Purified Water say "Deionized and ozonated for distilled water uses."

BIG MISTAKE.

I pulled out my phone and Googled distilled vs. deionized. The pH properties of deionized water are explained on this site:


So I have one expensive gallon of actual distilled water from a health food store nearby, and I'll be going on a quest for more of it tomorrow. In the meantime, I have no idea which of my gardens have gotten more Purified Water than Steam-Distilled Water, so I'll have to pH test all of them and try to correct the balance.

If your water had a pH of 5.6 to start, adding the pH buffered  AG nutes could have knocked it down into the 3s. The water here in Grand Rapids is pretty decent. I just use tap water. It works fine.

When I tested them last night, the lowest tested at 4.36, but I was able to bring up all the ones that were acidic into the 5.5 to 6.5 range. I haven't tried using tap water because I live in Florida, and I had come across this support article on the AG site mentioning Florida water:

ALL of my tomatoes are showing new signs of nutrient deficiency in the Sprout, Classic 6, and Bounty . I tested the water and found it too acidic again. I don't get it. The peppers and eggplant (in 2 Bounties and 1 Ultra) are getting the exact same water, but they're on the alkaline end of the expected range. I'm not sure if it's something the tomato plants are producing or what... The only difference between the peppers and tomatoes is that the peppers get 2 mL more of the Ca/Mg supplement, but I would be surprised if 2 mL had that much of an effect on pH.