Please help! PH too low

Auto flower grow here. 1st time grower. PH is super low. Using FF Ocean forest. Seeds germinating right now and will be ready to plant tonight so the pressure is on to get PH down.

Calibrated both of my ph pens to .1 accuracy

Soil runoff test at 4.39
Flushed the soil with 8ph distilled water (twice) and measured again at 4.76ph. Didn’t move much.

Now I’ve heard to not use any other nutrients or additives with the FF blends because they’re already packed with a bunch of nutrients. But what should I do?

Should I just keep running higher ph water through the soil until desired ph is achieved or would I start adding other ph raising mediums?

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PH issue are exactly why i dont use this soil. Others swear by it, i struggled with it. Yes, other nutes are not needed during veg phase typically. How did you calibrate your meter?? If my pH is that low, i mix higher pH water and keep flushing.

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Seen a lot of low PH posts re: FFOF.

Adding high PH water won’t do much for you. Top-dressing dolomite lime and watering in will buffer PH to a higher value. Follow package directions.

You could probably flush to get PH up into range but you will be removing all of the salts currently present in your media.


Very good point, didnt think about that :man_facepalming: i feel like FFOF had its day in the sun, but now there are better options around.


Will do. Thanks!

Yeah. Wanted the first time to be easy and researched and I found that it was most “popular”. I’ll make my own next time.

Alot of folks use Promix too.

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I’ll have to check that out.

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Yeah 4.3 ph that’s on the bottom of the scale very low. When calibrating pH meters the calibration is no better than our solution. I would get me a fresh clean bottle of 7 pH solution just to verify. It is easy to contaminate solution doing multiple point calibrations and not cleaning thoroughly between. An also store Solutions in a dark place. Just my thoughts good luck getting back on track.

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Thanks @kellydans. Yeah I have calibrated both of my ph pens and did find that the Vivosun meter has stayed calibrated but the more expensive Wiztech has already fallen out of calibration after one night. I’ve been measuring everything twice to make sure. I tried raising the ph of the soil with lime as directed on back of the bag (2to4tblspn) (tried to find dolomite, but store didnt have any) and it didn’t raise but to 5.17 so I added some more and I’ve got it to 5.3. I’ve been flushing the soil like crazy just to get to that pH. Gave the soil a break for the night and going to perform another soil runoff test a little later. Keep ya updated

Hey @Myfriendis410 I replied to @kellydans with the update. Thanks, bud.


Something they don’t tell you is storing PH meters in a storage solution. You can find it on Amazon: basically put a 1/2 tsp in the cap when you close it up. This keeps the (special) glass bulb hydrated correctly. Distilled water is not recommended as it will scavenge molecules from the glass bulb and damage it.

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