Do you rinse the ph probe between use? Nutrient build-up can occur there, too.

Quote Originally Posted by lampost
The fact that redtails was unable to save a ph-skewed plant scares me. Is it too late to sprinkle some dolomite lime on the surface and hope it will infiltrate the soil?
Fresh soil, and a transplant. If you're going to lose them anyway...
I've transplanted ladies in late flower to save 'em, but you could very well pay a price. If not careful you can break branches or roots, they can go hermie and might not finish completely before you have to harvest them. (fully formed nanners) If no stress, and all goes well...slow/stunted growth likely till harvest. Might even stretch a tad if there's enough nitrogen in the fresh potting soil, but buds will likely be underformed.

If getting desperate, and you know for a fact you are losing the soil buffers, (ph swings, nutrient lock-out) I might be tempted to grab a gallon of water, and add a cup of lime and disolve as much as possible. Add it to the pot slowly. Flush it through with another properly ph'd gallon of water, so it's not all sitting on the top layer...and keep your fingers crossed.