It is common for the seed leaves to yellow and fall off, so i wouldn't worry that much and see how the plants are developing. Just be careful to not over water those young plants. Let the pots get a bit dry between the feedings the first times so the substrate doesn't stay wet all the time. Have you checked the ph of the substrate a few days after mixing?
What is your target calcium concentration? I personally would not use much if any calcium chloride as fertilizers usually already contain a bit chloride as contaminants although i think it should be not much of a problem as long as you don't overdo it. Are you mixing your solution from Individual salts or do you use premixed fertilizer and amend it with calcium nitrate? And what substrate are you using if any? Tap water or r/o? Because in a limed peat based substrate there is already some calcium available. I use a self mixed and limed substrate similar to that of Dr Bugbee but with 25% vermiculite and 25% perlite instead of 50% vermiculite. I mix my nutrient solution with r/o water from individual salts (potassium nitrate, calcium nitrate, ammonium phosphate etc.) with a calcium concentration of ~70-80 ppm, and my runoff water is usually around 160-200 ppm calcium (tested with a calcium titration water test) over the course of an entire grow. So i could get away with even less calcium in the nutrient solution.
I have no way of testing the pH of the media as I only have a EC meter and pH meter for the water solution. I test the water pH and EC after adding the nutrients to the water. And I test the EC of the run-off to make sure it doesn't get too high. I always make sure the pots are dry/light in weight before I water again.
Yes it plays a big role if the lime is not powdered since it takes very very long for it to completely react. Longer than the few months till harvest. So it may well be that your substrate is too acidic since not enough was neutralized by the lime. I can't get powdered dolomitic lime too, so what i do is grind it with an electric coffee grinder (they are very cheap) until it is fine powdered. This works very well.
I've been thinking about how to grind my Dolomite Lime into a powder and I'll look into an electric coffee grinder. I found a place where I can buy a 25Ibs bag of powder Dolomite Lime for $7.25 and I'm thinking about buying it rather than buying a $20 grinder haha.
I would let it react for a few days but for this to occur a bit of moisture is necessary so it is best to slightly wet the mixture and mix it once again. But i think it should also work if it is directly used as long as it is thoroughly mixed since it doesn't take that long to neutralize if using powdered lime. Just water sufficiently after transplanting.
What EC do you start with? I have been giving this plant around the same EC everytime I fertigate, even the smaller plants get the same EC.
Its safe to say not to feed 1.3 initially but to build up to it.
So what's a good starting EC and how and when do I work up to 1.3?
Ok, your ph seems good, it will rise a bit the next days/weeks since the dolomite will continue to react. You could dilute the nutrient solution a bit to an EC of 1,0 if you want but i wouldn't worry too much as they are now at a size where their growth will soon take off and they will rapidly building bio mass. What kind of light do you have?
I have a 240w Kingbrite 3500k + epistar 660nm. I've been also trying to find a good VPD chart to make sure that's all in order. But there are so many different ones that give different VPD's. My plant is still a light green and 2 bottom leaves are getting necrosis and falling off. I hope it bounces back from whatever is wrong with it.
What is your temperature and rhumdity? And what distance is the light away? Because if it is very close it could be too much with leds.
Temp during the day is 78°f - 81°f with 70% RH and at night it can get as cold as 65°f.
Ok that looks good. All values seem reasonable fine so your plants should soon take off.
