your girls are not looking so hot
in the picture it looks like purple veins in one of the leaves
this is a P or possible mix of a few def
Phosphorus (P) deficiency:Fan leaves are dark green or red/purple, and may turn yellow. Leaves may curl under, go brown and die. Small-formed buds are another main symptom.
Phosphorus deficiencies exhibit slow growing, weak and stunted plants with dark green or purple pigmentation in older leaves and stems.
Some deficiency during flowering is normal, but too much shouldn't be tolerated. Red petioles and stems are a normal, genetic characteristic for many varieties, plus it can also be a co-symptom of N, K, and Mg-deficiencies, so red stems are not a foolproof sign of P-deficiency. Too much P can lead to iron deficiency.
You have not feed them anything? Which roots did you use? 707 or the coco coir mix? 707 is strong soil that should keep the girls feed. You really need to get a ph meter cause when you feed them you have to ph the water unless you buy canna ph'd already feed.
Ebay had cheap ph meters for 15 bucks.. Look back at my threads.....no matter what you have (3 plants-----200 hundred) you have to ph your stuff and do it often. Everything you put in the water pushes things up and down. So its a little tricky if you dont really know and you r just kinda guessing.
I would flush the girls heavy flush and then start a light feed program.
but do some more research and see what everyone else says:
I dont know much so I just give little help where I can
good luck bro