Issues with Rockwool PH

[ElJefe4200]

Having issues over a number of weeks now in my rockwool. My ph runoff is consistently 6.8-7.1 and the plants look sad, stunted and heavily deficient. They have had 2-4 day stretches a few different times where leaves start to quickly turn normal and healthy again, with praying leaves etc only to regress and look awful again for weeks at a time. Any advice on what the issue could be, and how to fix it is welcome. I'll post pics as well if requested.

Thank you all for your time.

 

[Dirtbag]

Gonna need pics and so much more. Exactly what are you feeding as in starting water? calmag? nutes? ph up? ec/ppm? input ph? runoff ppm?, number of irrigation cycles and duration of each cycle, How much runoff, how much dryback, sterile or live? how much wool are they in, Hugos? slabs? plant size, room temps, humidity, lighting,.. tell me everything.

 

[JaneSupreme]

Definitely need to provide much more detail & pics would be great

 

[ElJefe4200]

Alright I'll get some pictures the next time I'm at the shop. Starting water is close to RO level but its well water. Under 25ppm. No cal mag, at firstI was using straight megacrop then I tried some veg+bloom that I had lying around for the last 5 or so days. EC going in is 1.2, coming out is 1.1 or 1.0. Ph going in is 5.6, coming out is 6.8-7.1. Irrigation is once a day currently, because my solenoid broke but soon they will be going into a room where they can properly be watered at the 105ish ml once an hr type setup that ive heard this medium enjoys. Runoff is substantial because of the single watering per day, but the tops definitely dry out between waterings. Plant size is maybe 20 inches. humidity is around 60-70 depending on how close or far from waterings it is. Temp is 80-82f. Theyre in Hugo 6x6s. lighting is two 350w cmh per tray each tray has about 40 plants.

 

[Dirtbag]

Temps are a little high, under 80 would be better.
You are also way short on calcium. If starting with 25ppm you need to bring that up to 150ppm or 0.3ec with a calmag product before adding nutrients. Calcium is essential for nitrogen uptake and a pile of other things.
Megacrop V1 or V2 is apparently ok stuff.. But a complete balanced base nutrient is important. Not sure what grow/bloom you're using, can you elaborate on that? And are you using ph up?
How do the roots look on the bottom of the blocks?

Ppm going down and ph going up means they're eating at least. But they would probably benefit from more irrigation cycles, as many as it takes to dry back about 40-50% between cycles. And again, more calcium.

 

[ElJefe4200]

veg+bloom is what the nutrient line is called. I use no ph up ever because my water comes in close to pure water ph so usually around 6.8ish. Roots look good, white, fluffy etc. Megacrop says you shouldnt need to add any calmag and I've never had an issue with multiple large coco cycles with a calmag issue is this something that is specific to rockwool?

 

[Dirtbag]

veg+bloom is what the nutrient line is called. I use no ph up ever because my water comes in close to pure water ph so usually around 6.8ish. Roots look good, white, fluffy etc. Megacrop says you shouldnt need to add any calmag and I've never had an issue with multiple large coco cycles with a calmag issue is this something that is specific to rockwool?

Which version of megacrop do you have? V1 and V2 need more calcium. V3 they say you dont.. but I'm not convinced it's all fully soluble calcium. Pretty much any time you start with RO you should always use Calmag to bring the EC up to 0.3

Pics will probably help diagnose if this is your issue.

 

[ElJefe4200]

Good to know on the calmag part, I'm using the most recent formula from MC (or well, I was till switching to veg+bloom for a few days to see if a dif nutrient line would help).

Ill get pics asap probably some time tomorrow mid afternoon when I'm back home from the shop.

 

[ElJefe4200]

This there a calmag you recommend thats highly soluble?

 

[Dirtbag]

Good to know on the calmag part, I'm using the most recent formula from MC (or well, I was till switching to veg+bloom for a few days to see if a dif nutrient line would help).

Ill get pics asap probably some time tomorrow mid afternoon when I'm back home from the shop.

Well if you're not using megacrop now there is no sense in turning this into a megacrop thread lol. Plenty of threads on that already.

As for Calcium, I tend to use the same brand as the base nute line I'm using. But really any calmag should suffice. Personally I use botanicare products at the moment

 

[ElJefe4200]

The requested pictures

 

[Dirtbag]

Pretty textbook Mg deficiency from the look of those pics. Kind looks like a K def but it might just be advanced Mg def, they look kinda similar, but since you arent using calmag I'd guess they are really low on Mg. Are you able to post pics of the labels on your fert bottles? I'd be curious to know what's in it.

 

[ElJefe4200]

I added 150ppm of calmag to the feed today, so hopefully that fixes things over time. Whats the reasoning for the PH in the runoff being so high?

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This ^ is the website for the nute line. I dont have the label anymore just bags of powder.

 

[Aqua Man]

@Dirtbag has ya covered on everything I use megacrop and he is absolutely accurate about it not that your still using it.

One thing that jumps out at me is that ph swing have to get that under control and my gut tells me it's the lack of feeding frequency. I would listen to @Dirtbag he really knows his shit and then some.