New Grower Light stressed, bleached plants?

[musicvoyager]

If it were bleaching it would start on the top most leaves and would work from the center of the leaves outward toward the tips. I think you're seeing the early signs of over fertilization given the deep green color of your leaves and the fact it is starting on the leaf tips. What have you been feeding them and at what strength?

Nothing, as I said before, my soil is 40% worm castings, 30% perlite and 30% vermiculite.

I think it might be damage by the fans, I have already fixed them in brackets on the side and at different heights.

When the lights go out, the plants go absolutely crazy down, I've never seen something like that, and I added the hydro rocks just recently. Some leaves might have been hitting the rocks and the fan supports. While I am careful to avoid any sort of contact, during lights off I wasn't absolutely sure. Let's see how they are next week. The color is absolutely beautiful, and the smell they are starting to produce is very citric.

 

[Muddy]

Your soil mix is the problem. I've grown a lot using worm castings and they shouldn't be more than about 20% of the mix, tops. Worm castings are high in nitrogen, which is what is giving your leaves the deep green color and causing the tips to burn. A good mixture for worm castings would be 5 parts sphagnum peat moss, 5 parts perlite and 1 part worm castings, plus dolomite lime to buffer the pH. I also think with straight castings you may run into some pH issues. Do you have a pH tester? If so, what is your pH reading? If I remember correctly I believe castings have a low pH, around 5.5 or so. Weed needs a pH between 6.3 - 6.5 to grow best.

 

[musicvoyager]

Your soil mix is the problem. I've grown a lot using worm castings and they shouldn't be more than about 20% of the mix, tops. Worm castings are high in nitrogen, which is what is giving your leaves the deep green color and causing the tips to burn. A good mixture for worm castings would be 5 parts sphagnum peat moss, 5 parts perlite and 1 part worm castings, plus dolomite lime to buffer the pH. I also think with straight castings you may run into some pH issues. Do you have a pH tester? If so, what is your pH reading? If I remember correctly I believe castings have a low pH, around 5.5 or so. Weed needs a pH between 6.3 - 6.5 to grow best.

Oh man... there is more than one way to skin a cat... Way too many contradicting ways on the internet... I am in no way saying your advice is wrong, it's highly appreciated. I just followed a book that said that a good casting mix would be 40-30-30. Then someone in a forum said that casting retain too much moisture, so no need for vermiculite, now you are telling me that casting are too high in nitrogen and shouldn't be used by more than 10%.
I have PH strips, they marked 6.5 last time I checked. Will check later today after watering. Anyway, today the problem is even worse, and doesn't look like it is the fan problem, but more in the way of the problem you pointed.
The only thing I have changed is the watering schedule. Before I was watering everyday with water run for at least a couple of hours with air stones, 100 mL per pot. I was having algae on top of the perlite, that's why I added the hydro rocks, and changed water schedule to water every other 2 days, 200 mL per pot, the soil is still somewhat wet after 2 days. I think I am going back to water everyday with a little bit of water.
If I am having nitrogen problems, what are my possible solutions?

Picture is with lights off, that's why the leaves are all down.
View attachment 133199

 

[Muddy]

What you were reading was probably pertaining to photo period plants, not auto flowering ones. Autos are a lot more nutrient sensitive than photo plants. Where most photo plants can take full strength nutrients, most autos can only take half strength at the most, some no more than 1/4 strength, depending on the strain. You are also watering way to often. Weed like to go through wet/dry cycles. Keeping them as wet as you are cuts off oxygen to the roots. Learn to water by the weight of your pots. Get a feel for them when they are almost dry and only water when they feel like that. Then give them enough so that about 10% runs out the bottom of the pot. Under LEDs I would expect you can go at least 4-5 days between waterings.

Giving your plants a heavy flush could provide a temporary solution but I think the N level will only rise again within a short period of time. Transplanting might be a better option. What size pots are they in now?

 

[autoberry]

Nutrient

%​

Nitrogen 2.34

Phosphorus 0.56

Potassium 1.00

Calcium 2.28

Magnesium 0.42

Sulfur 0.56

Worm Casting Standard Nutrient Profile;

With a 40% worm mix.........the potential for more nitrogen to come forward is huge,......and watering will exacerbate this . However if your WC mix has a similar calcium (Buffer) content,.....ie like the profile above,......to high a N level without a buffer, will cause low PH. You could counter this with cal.mag def tonic ??........what dose Muddy think ??..........AB..........if not, and there young enough, a soil dilution and rebalanced seems possibility.......AB....

 

[musicvoyager]

You are right, what I read was for photo period plants. Never thought autos would be that different.
I am using small pots, about 3.5L or 0.8 Gallons. They are tall and for orchids. The guy I bought the seeds from uses 2L soda bottles successfully, so I thought a similar approach would be alright for my autos.
The reason I water so often is because I use very oxygenated water, as I said, run with air stones. So I am incorporating oxygen everyday. As I understand, problem is stagnated water, not excess of water. The leaves don't show signs of overwatering. Bubblepon systems have the roots immersed in water with no problem at all. More watering might made available Nitrogen more dissolved? Kind of a continuous flush?
I have very good drainage, so I can try to give them a flush, although they should start flowering in the next couple of days.

I cannot find good numbers of NPK contain in worm castings, no idea, got this: "Worm casting NPK numbers found on the internet range from NPK 3-2-2 to 0.5-0.1-0.1. Worm castings also usually contains high levels of other macronutrients and micronutrients, and while the three main nutrient levels may appear low, there is usually plenty of micronutrients in worm castings, and the general nutrient availability is high"

 

[Muddy]

You can't compare a hydro grow to a soil grow. While bubbling your water is good, too much water is just that, too much, and watering every day or every other day will only eventually lead to issues.

Those are very small pots so here's what I would suggest. Get some 3 gallon pots and a good soil like Pro Mix HP. Give them a good flush, wait a day for it to drain off, then transplant them into the bigger pots with the Pro Mix. This should then allow you to feed some mild bloom nutes once they finish their veg period. I'm afraid that with the high N and lower P and K of the worm castings your buds won't reach their full potential. It should also help reduce the N level to a point where the plants can tolerate it.

 

[musicvoyager]

Ok, I just read your post that watering will exacerbate the problem. I find it curious though, that the problem increased when I started increasing my time between waterings. My plants are now in day 19th of growth. I am going to check the PH later and post the results. Unfortunately, I have no idea of the composition of my castings.

Edit: PH is 6.5

 

[musicvoyager]

Where I live I cannot get any brand name soil. Just some "potting soil" or something generic like that. Even if I don't get full potential, at least I know from this grow what I shouldn't do on my next one.