I'd ease-up on throwing everything under the sun at your plants. You can kill them with kindness. Any Dr. Q's Filthy Rich potting soil available where you get the Black Gold from?

Potting soil and garden compost are two different animals, and are buffered differently. Potting mixes are usually buffered to around 7.0 and compost is buffered at 6.0 ish. Over time, both mixes will lost their buffering, and ph will start to plummet.

Did you add perlite to the mix? Black Gold has some excellent perlite. (I use it)

There is no reason to bubble your water before adding to the soil. When you water, the suction it creates in the soil draws-down the air anyway.

Careful using MagPro. Excessive magnesium (also called mag. sulphate - epsom salt) can and will lock-out the other nutrients.

In the 80's is fine. I don't recommend this to newby's, but during the summer my ambient flower shed temps can easily reach 100.

If possible, lower your 400 watter to around 16 or so inches.