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"miracle grow soil, but its a year old"
Buy Pro Mix, Scotts, B'Cuzz, add some perlite.
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"the PH of the soil was 3-3-3 i believe"
Do you have a PH pen to measure the PH of your water after adding nutrients. I believe that Medi 1 is correct, your original problem was nutrient lockout from PH imbalance. If you didn't balance your flush water's PH, or didn't use distilled water, you still have a PH problem.
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"i just repotted to a 8x5 pot but sadly 1/4 of her roots got damaged"
Don't worry about the damaged roots, the residuum will bud secondary lateral roots and your new root ball will be denser. Good move.
If you used Miracle Gro fertilized soil in the new pot then repot immediately with a simple peat, perlite, vermiculum mixture - brands above. Break up the root ball and discard the new MG, keeping the inner root ball. The MG will continue to give you problems, do not fertilize.
Download the Equipment chapter of Weed Science and look at the root pruning buckets.
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"i do not have a PH test kit unfortunately"
The Oakton 1 or 2 are around $75 to $85 online, reliable and fast readings.
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