Low Soil PH how can I get it up?

I’ve 2 plants with low ph. At about 5.4 now.
Have them in fox farm ocean forest. After 8 weeks I started giving nutrients and now soil is low in its ph.
How can I get the PH up quick. Started flower stage about week ago.

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That sounds strange as as ocean forest shouldn’t have a low ph. What is your water goin in? How are you measuring ph?

10 gallon fabric pot. Using digital ph meter.

I water with distilled water

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How many weeks have you been feeding and what product are you feeding?

A low pH in FF soils is usually due to a salt buildup.

Only fed it twice. Once was a gallon split between the 2 and then second time was half gallon split.

Advanced nutrients

Getting ready to leave for 7 day tomorrow. Need to fix.

Add lime

How much?

It will take about 4 tablespoons of lime per 1-square-foot to raise the pH level two points. Start with 4, remeasure, adjust if required. YMMV

I’ve also used cal-mag. Does that make a difference?

Are you adjusting the pH of your feedings?

Yes. Check with digital ph meter. Always keep at around 6ish

Calcium Nitrate raises pH, Magnesium Nitrate lowers pH. They generally counteract each other so it shouldn’t make a difference.

But ck it yourself. Measure some water, add some Cal-Mag, remeasure the water.

The zkittles is in the worst shape. GG4 is just little limp

You are correct in that it shouldn’t. However it is actually very common. Many posts about it here. In fact many have moved away from it because it happened too often. I believe the stability of the buffering has a limited shelf life. If the bag sat for awhile plus the grow time, the buffering gives out.


6 for soil is a little low. It should be 6.5 ± Is the drop in ph related to nutrient use or was it dropping before the start of nutrients?

When applying lime to an existing plant, how would you apply. Sprinkle and water? Or mix into water?

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