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I agree that this is definitely some kind of middle stage nutrient deficiency. It could be Nitrogen or Sulfur deficiency. As the symptoms are very similar.

Thanks!

deficiencies could also be caused by nutrient lock or build up salts. check the quality of your water and leech the soil(put a plant into a bathtub, or over a bucket and water heavily with 3x the volume of water as the pot.

Pretty sure that it's not nutrient lock. As these girls are not constantly being fed nutrients. On off nutrient feeding days, the water is pH balanced and we make sure there is a decent run off.