Acidic runoff ph

Hi Im using a coco/peat mix for my media and the advice i got on this forum says to ph my water/feed at around 5.8-6.0. For some reason im having an issue with my runoff being too acidic at 5.0-5.1. I tried two different things that were suggested on this forum. First thing I tried was watering/feeding to more runoff at a ph of 6 and I was getting about 30% runoff. I did this for a whole week and runoff is still showing the same result. I also tried ph’ing my water/feed to 6.2 and 30% runoff but I still got the same runoff reading. I have another plant in the same exact media and runoff ph measures at 5.6-5.7. I did try experimenting with ph on my other plant and increasing or decreasing ph of water is effecting my runoff so i’m not sure why the runoff from this plant is not going up. The plant looks green/healthy but both plants are in flowering and they’re both the same age and the one with the correct runoff ph is waaaayyy ahead in flowering. I can see a lot of pistils and getting slightly bigger every day while this plant has only a few pistils showing. I’m open to any suggestions becuase at this point, im out of options and can’t think of anything else to fix this. Thanks

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I do use ph up every time i water/feed but its not helping

Peat is known for becoming acidic. Blueberry farmers use to make the soil acidic.
In small amounts or for starting seeds its great for moisture retention, but large amounts in the long grow will make an acidic environment.
You might pH the water to 7 and see how it does. Make sure to water so as to get a good run off and keep it in range.

Are you also taking PPM reading when getting runoff ph?
Is there a correlation between the plants and their respective ph & ppm?

both of them are within700-750ppm.

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Crushed limestone is a common additive to raise ph. Finely ground limestone (calcium carbonate) can be worked into the soil.
If you have very hard tap water with lots of calcium, use it.
Rootzone enhancers with microbes, bacteria and fungi help buffer ph swings and I belief can increase ph. These should be started early on so not much help during flower.
Adding lime will also take time to break down.
At this point I think increasing the feed ph to 6.5 is the best best. The roots at least will receive a fresh batch of good ph.
PPM of 700 is a little low for a flowering plant. Feed it a bit more.


is 6.5ph within range for a coco/peat mix? because I was told to use a ph of 6.0. Or is it to help balance the ph in the media?

I’m on my first grow and I’m also using soil so I’m not sure if this will help at all. But I had my reading in between 5.5-5.9 between 5 of my plants. It took several waterings of me adding pH up to a 7.0-7.1 ph reading before watering to finally get my soil ph up to par. 6.0-6.5 ish.

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But were you at least seeing slightly higher ph with each watering? even if its just a 0.1 increase. Im watering my plants every day due to the weather we have so I gave it about 12 waterings to runoff in total and runoff was either staying the same or going even lower.

The first time or 2 I don’t think I did is why I upped it to a 7ph instead of just a couple points higher. I first started with like 6.something then raised to 7 after not seeing much of a change. But that’s just my situation. Like I said this my first grow and so far it appears I have some happy and healthy little girls. But I would wait for a few folks with more experience to chime in before making any significant changes. Would feel absolutely terrible if something bad happened after following my lead when there are many folk in this forum with allot more experience than I have. :+1:

This is what I got so far. Zkittlzz photos going on 6 weeks running growers choice roi-e720 led and master controller , 5x5 ac infinity with 6 inch exhaust, co2 , sohum soil, ff nutes

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I use coco with perlite. You are correct, the normal ph is 5.8 - 6.0 for all inputs. I suggested 6.5 because the runoff ph of 5.0 - 5.1 is so low. During flower, especially mid to late flower runoff ph of 6.2 ± is where I want to be. I’m not sure why your runoff is so low. Peat will lose it buffering over time. I think Premier says it should have a stable ph for 6 - 9 months. Native / untreated peat has a low ph of 4.5 or there abouts.

I can’t find understand it either to be honest. Its my first grow and this is making it more difficult than I anticipated. even though the runoff is low, its still looks surprisingly healthy. I’ll probably try a different mix for my second grow. I’m thinking of going full organic with biobizz mix and nutrients. I heard good things about them. The issue im having could be because im using a lot of products from different companies. Not sure if it makes a difference but im using products from 4 different companies. I have calmag from biobizz, Im using base nutes from advanced nutrients the ph perfect line, i’m using advanced hydroponics ph + and - and some weird ass mix that I never heard of. I guess we’ll see how this goes and be more prepared for my second grow. this is how its looking. Disregard the droopiness as its 8pm and around this time it starts to droop