how to correct low ph in coco?

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sangmang

Active Member
Slurry tests of my coco shows 4.9ph. I was over feeding these plants a couple weeks ago and my coco runoff was up to 1200ppm so I flushed with very light nutrient solution down to 450ppm.

I believe the salt buildup caused a ph drop in the rootzone which started causing a calcium deficiency. So ive been feeding @ 500ppm (top drip dtw 3x a day) just calmag and base nutes(emerald harvest 3 part) at like 6.4ph but the slurry tests still come out at 4.9-5ph. I'm at day 38 in flower and it seems like growth is a bit halted.

Any recommendations on how to raise my rootzone ph?
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Star Dog

Star Dog

Well-Known Member
Feed it with ph 6.0/6.5 to run off and leave it, what ph runs out is irelevant.

My run off is 1.3/1.4 and my plants are healthy.
Idk what what your experience is but I feed seedlings with 0.6 then raise it gradually to 1.1ec.

Are you feeding until it runs out of the bottom of the pot?

What your temperatures and humidity the plants look nute burnt/salt build up to me.
 
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sangmang

Active Member
Star Dog said:
Feed it with ph 6.0/6.5 to run off and leave it, what ph runs out is irelevant.

My run off is 1.3/1.4 and my plants are healthy.
Idk what what your experience is but I feed seedlings with 0.6 then raise it gradually to 1.1ec.

Are you feeding until it runs out of the bottom of the pot?

What your temperatures and humidity the plants look nute burnt/salt build up to me.
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Yes I had salt build up and flushed down to 450ppm. I feed to 20% runoff daily. Fabric pots. I understand not worrying about runoff ph but a slurry test is different and reveals low ph at the roots.
 
getogrow

getogrow

Well-Known Member
sangmang said:
Yes I had salt build up and flushed down to 450ppm. I feed to 20% runoff daily. Fabric pots. I understand not worrying about runoff ph but a slurry test is different and reveals low ph at the roots.
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Ph tests are a joke.
That to the side. From what these guys are saying , and i agree....that your problem is fixed and just keep giving them lower ppm until they are ready for more. Too much food cannot be reversed , only fixed.
 
Star Dog

Star Dog

Well-Known Member
I think you are trying to solve a problem that doesn't exist?
If you rinse back the ec and maintain it with the proper ec/ph there's nothing more you can do?

You can't undo the damage once it's done.
 
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sangmang

Active Member
Star Dog said:
I think you are trying to solve a problem that doesn't exist?
If you rinse back the ec and maintain it with the proper ec/ph there's nothing more you can do?

You can't undo the damage once it's done.
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Thanks. It just seems like the calcium deficiency is slowly worsening. The twisted growth is a new symptom as well. Temp is 75f and rh is 45-55 fyi. Rootzone is kind of cold though around 60f. I'll just keep feeding properly and see what happens
 
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sangmang

Active Member
I'm feeding 3x a day about 400ml each feed and coco is always wet. You recommend I keep that up? 1 gallon pots
 
Rurumo

Rurumo

Well-Known Member
That's pretty cold, that alone will result in slowed growth. Here's the thing, when you feed at say 6.5 and the runoff ends up at 5.0, the plants were exposed to that full range of PH and were able to absorb nutrients across the range-that's why you don't need to really worry about the runoff. Just be sure you pour enough nutrient solution through each time to get plenty of runoff and be sure you're watering through the entire pot. Some people water too quick and don't saturate all the media. I'd pour some nutrients through each pot first, wait a couple minutes, then finish watering.
 
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sangmang

Active Member
Rurumo said:
That's pretty cold, that alone will result in slowed growth. Here's the thing, when you feed at say 6.5 and the runoff ends up at 5.0, the plants were exposed to that full range of PH and were able to absorb nutrients across the range-that's why you don't need to really worry about the runoff. Just be sure you pour enough nutrient solution through each time to get plenty of runoff and be sure you're watering through the entire pot. Some people water too quick and don't saturate all the media. I'd pour some nutrients through each pot first, wait a couple minutes, then finish watering.
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Thank you. Yeah I know, I'm thinking of switching to DWC to control root temp better. I don't have much recourse right now at warming up the coco. The drip system feeds 200ml per minute to 3 spots on each pot.
 
Rurumo

Rurumo

Well-Known Member
sangmang said:
Thank you. Yeah I know, I'm thinking of switching to DWC to control root temp better. I don't have much recourse right now at warming up the coco. The drip system feeds 200ml per minute to 3 spots on each pot.
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Oh, gotcha, that should be fine, just be sure you get plenty of runoff. Coco is awesome because you can constantly "flush" it out with your target ppm/ph nutrient solution.
 
Star Dog

Star Dog

Well-Known Member
sangmang said:
I'm feeding 3x a day about 400ml each feed and coco is always wet. You recommend I keep that up? 1 gallon pots
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Idk maybe with it being a bit cooler a good soak once a day might be better.
I feed every 3hrs atm but my nutrient is heated and it's warmer around the pots.

Apparently root rot is more widespread than I realised I wouldn't want to recommend multi feeds without being sure and I'm not with your temperatures?

I can't believe I'm considering root rot until yesterday I didn't think it was a coco growers problem.
Anyone?
 
D

Destroyer of chairs

Well-Known Member
sangmang said:
800 at the highest
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My recommendation is more Runoff. More than once have I fixed my problem by doing this.
If u did increase it after the build up, great! If not I bet it will fix things.

On a side note I've read that salt buildup happen easier in fabric pots, though I have no personal experience with it.

Edit. And also get environment somewhat in check.
 
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sangmang

Active Member
Destroyer of chairs said:
My recommendation is more Runoff. More than once have I fixed my problem by doing this.
If u did increase it after the build up, great! If not I bet it will fix things.

On a side note I've read that salt buildup happen easier in fabric pots, though I have no personal experience with it.

Edit. And also get environment somewhat in check.
Click to expand...
I just ordered a little 400watt oil heater that I think I can fit in the bottom of the tent. Hopefuly that gets roots warm enough. Otherwise my vpd and air circulation should be good.
 
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