2 week old plant showing discoloration in bottom leaves.

Setup.
3x3 tent.
Lights 2x qb96 v2 running at 136 watts 18" from plant tops.
Driver HLG-320H-54.
Home Assistant w/ Govee H5074 , humidifier , Fan , and Heater automated to keep things in check with smart switches.
Plant 2 weeks old.
Growing in rockwool
Temps floating between 70-75f
Humidity running between 55-63%
VPD kept between 0.6 - 0.97 kpa
Running Florabloom/Floramicro 1 tsp per gallon.
Given at every feeding.
Buying 1 gallon RO water for feed.
Ph: 6.5 Water once a day. had a suggestion It was a PH issue. Took my PH20 and did the calibration on it and retested and 6.5 still.
Saw some algae 2 days ago which means I’m overwatering a bit and covered it with tinfoil since I didn’t have anything else safe to cover it with. Saw this on both the bottom big leaves today and thought it was a Calcium deficiency but not sure if I’m burning the plant with nutrients since I’m using it every feeding. Only seeing this on 1 of the two autoflowers.

Any help appreciated.

From what I can tell, they look overwatered as you already mentioned.
Speculating: Try something else but foil, if it can't breathe properly maybe theres some root issue developing.
If you're planning to put them in soil -> do it, might help them recover.

Other than that I'm just wondering if FloraBLOOM are really the right nutes for your stage, but I'm not familiar with that product.

Thank you for the reply. I ended up transplanting them into my hempy buckets early and after doing a bit more research it seems the PH was a bit too high for the rockwool I started them in. the plant is looking better now in the 100% perlite hempy bucket.