Two week old Blueberry starting to yellow

[Rusty Trichome]

.4) Is there a consistent fresh air supply?no

Any way to arrange 24/7 air circulation? Builds stem strength and circulates the CO2. If pots are too small for overnight back and forth air flow, (drying out the pots) move fan nightly so the air circulates...just not directly on them.

.6) What are the bulb wattages, kelvin ratings, and schedule?24/7 2400k i think...cool white blueish colour

Mine are usually in the 5000k-6500k range.

Your medium:
.7) Specific brand and type of soil, (coco, peat based soilless...) and anything you've added to it. (vermiculite, perlite, worm castings...)miracle grow potting soil and perlite 80/20 mix
.8) Size of container.750ml

I've never used a seedling mix for longer than a couple weeks before transplant into a regular potting mix, but it might not be ph buffered for long-term. (a full vegetative cycle)
Peat is acidic, so when buffers fade, your ph will plummet. Most nutrients will pull your ph down too. I notice that lower down, you mention nothing available to test ph. It's a rather important tool. If you can't afford a ph pen and calibrating solution, an aquaruim ph test kit would give you a fairly good idea. Or, Google your local water quality report(s) for quality, ph, what kind of chlorine they use...
It's handy info. (if your locals post the info)
For a peat-based grow, you'll want ingoing water to be within a 6.3 to 6.8ish ph range. Above or below that, and you'll start freaking-out the roots and start locking-out various nutrients.

14) How often are you watering between feedings, and how much per watering? when its dry no ph tester....yet

Don't let them dry-out too much, or for too long. If when you water, the water just flows right out, you'll want to water a little more at a time, or a little more often. If the water does flow right out, add the water slower, and less at a time. Try to establish a working schedule and consistent quantities.

22) Have you seen signs of insects in the growroom? small flys

Likely gnats. I leave mine alone in the outdoor shed, and use a No Pest Strip indoors.

Likely the leaf bronzing is from the MG nutrients. That's about as bad as it should get, but your new growth tells you what's going on now, so let us know how it's looking in a day or two. If the bronzing worsens, give a holler.

So...you'll probably want a regular potting soil before your next transplant,
some nutrients for vegetative stage, (look around in the growlogs for what others are using with success.)
some nutrients for the flowering cycle, (same as above)
a way to know your water ph.

Other than perhaps lowering the fluoro tubes a tad closer, should be good to go. Effective light from fluorescent tubes is like 3-4 inches. It's quite possible the lower leaves are already yellowing from getting insufficient light, due to the lights being raised. Get 'em as close as possible without burning growing tips. CFL's extend further, but all you'd have to change is everything, lol. Fluoro tubes work, just less effeciently. (I still use 'em for seedlings and clones)