Just not sure what this is. Manganese? Calcium? Mostly on the lower leaves, but seems to be spreading. Details; -Ebb and flow, with rockwool (which has been a pain) -Keeping PH of nutes ~ 5.6-5.8 -Using Botanicare CNS17 Bloom and CalMag -PPMs @1000 -Trying not to water too much (1x/day) since rockwool hangs on to moisture I trimmed of some leaves that had this pretty bad, but coming back now.
Forgot to mention this is 4 weeks into flowering. I did some heavy lower-leaf trimming so I could pack the plants in more....afraid this may contribute to this.
You say your not watering to much and you water once everyday??!? If so then it defiantly over watering ...
Thats one theory I had, considering the rockwool. But in the pics I've seen of overwatering this doesn't seem to look the same.
Calcium deficency maybe. Mine will do the same when I keep my ph down likethat for too long as cal and mag aren't that readily availiblr at that low of a ph level. For hydro recommended ph is between 5.5 and 6.5. Your plants take in different nutes at different ph levels so if you keep it below 5.6 and 5.8 they aren't being allowed to take in everything they need because it's not all available if that makes sense. I let my ph slowly drift to about 6.4 from 5.5 before dropping it again. Just google ph nuttrient availability chart. Btw I'm doing ebb and flow too but hydroton not rockwool.
Tap water, @110ppm. But to be safe I may switch over to RO. I scoff at the use of RO for lower level PPM tap water, but it could be something else like chlorine. Time to play it safe. I never heard of letting PH drift to the low 6's for hydro, but it definitely makes sense to do so. I kind of changed gears today. My diy ebb and flow tray had some sitting water and now there's a bunch of small, black larvae, guessing from those small annoying fly's. Fuck it. Going back to DWC with a bubble tupperbin (had good luck with it before). Going to let the water just touch the bottom of the netpots, so the rockwool won't be submerged. Added an airstone to the bottom of the bin too. Things are either going to turn around or go down the tubes. I don't have too much rooting outside of the netpot/rockwool so things could go either way. I REALLY wish I wouldn't have used the 4" rockwool block. Maybe a small piece for starting out from seed, but not the block.
It's not over watering at once a day lol that just seems silly. but I def think it's the calcium. back when I had the same problem i added some calmag+ to no avail until I let the ph up for a few days and all symptoms were alleviated. Now I don't even add it my. Plants get enough with the full gh flora line as long as I let ph go up and down
If your using tap water you shouldn't even need calmag mos municipal supply's have some already but I'd use it til this is over to be safe. Black larvae isn't good at all but I'd get some azamax in your res for a couple waterings instead of going back to dwc as it can present many more new problems. I've heard of people use milk crate bottoms to get plants out of siting water in ebb but I just loosen my threads on my fittings so it leaks into my res a little and it drains out fine. For the deficiency tho I'd just try to get your ph between 6.2-6.4 for a few days and see if it starts to go away. I'd bet it at least won't get any worse if you do just that.
I have some panda film I cut into circles that fits over the round netpots. I will try the ph thing...
You sure you need that calcium? I don't see it in the botanicare CNS17 nutrient calculator during flowering. But as I said in your other thread, you need to put your rockwool on coco mats, and I wager your plants will perk up once the rockwool is allowed to dry out. Gnats is a sure sign of too much water.
Yeah I noticed the same thing....wonder why they don't include their calmag product in the bloom phase. Hmmm.
I'm pretty sure it's because it has almost as much nitrogen as calcium and more nitrogen that it has magnesium. Read the label is derived from calcium nitrate magnesium nitrate and something else for iron n trace minerals I think. N delays flowering and can cause hermies so I'm sure that's why they don't suggest it. I stop using shit like hygrozyme for flower even because of the residual N it can leave. With your tap water around 100 ppm I think you said you really should be fine without the calmag. let me know how the slightly higher ph is treating you!?
So is the N in Bloom (2-2-5) vs. ripe (1-5-4) a problem then? Or are you talking about more N than that? I'll post progress pics soon. I think things are better but I changed a lot of variables. Went to the DWC tupper bin (with the water JUST touching bottom of rockwool in the netpots), added an airstone to promote root growth, and started using RO water. I think where things went wrong is that I never had much root growth OUTSIDE of the rw. Re-reading on proper use of rw people do what you mentioned, have the rw sit on hydroton or a coco mat so the roots have that medium to grow into. So I think my cube of rw kind of became an air-pot where the roots never grew out of the rw. This was made worse by a short veg cycle where the roots didn't develop enough, like 2-1/2 weeks. My bad.
I thought you were supposed to slowly stop cal/mag in flowering in coco at least. Is it different for rock wool?
Ok, some pics below. Goal of the grow was to do a small SOG with single cola of different varieties. Doing Chrystal, Cheesewreck, Jack Horror, and White Widow. It was risky doing 4 varieties but with decent training in the beginning I'm happy that their all about the same height. Pic #4 shows the netpot barely touching the water. Pics 5&6 show the difference in root development. Pic 5 shows that instead of long ropey roots the rw/netpot is covered in many finer roots as a result of natural "air pruning" vs. having a nute base reservoir for the roots to grow into. I converted over to putting the rw/netpots in the dwc container a couple days ago. Plants seem healthier and happier. The roots in the last photo are probably 2x what they were a couple days ago. I'm letting the ph creep to around 6ish per n4ma4l's suggestion (thanks!). Yep, I know I need to cover up the clear reservoir.
The net pot makes it even harder for the rockwool to dry out because it encases like half of it in plastic. Rockwool does best as a standalone.