Apparent MG problem but not sure

Hey Guys, I'm growing 9 plants in a 4x4 tent. 600w dual spectrum, extraction fan and 2- 6 in. desk fans. Temp and humidity are within correct range. I just went into 12/12 3 days ago. I had a lockout problem a few weeks ago caused by low ph in the soil. Sorted that by transplanting into bigger pots and using Plagron Bat Mix. Things got better after that but there was a residual yellowing of leaves. It appeared to be nitrogen def.so i foliar sprayed with nitrogen because Bat Mix is so high in nutrients but low in nitrogen.
Things cleared up for a while and they seemed healthy and growing well. Now i'm getting yellowing leaves with brown spots in places, which seems to be an MG def. I foliar fed with epsom salts last night. 1 smallteaspoon to 2 liters of water, on 3 plants to see how they would take it.
The plants i fed are a bit droopy and some of the leaves are shiny and some are not. I noticed that the yellowing on some of the other plants is continuing just on the edges, and the leaves are lightening in color generally. Can anyone please help me out.



Bambu

Any chance you have fungus gnats? They cause damage that is similar to MG or K deficiencies. The open wounds on the root hairs caused by larvae feeding allow fungus attacks to flourish, which looks like N deficiency much of the time...

Photos would definitely help!

Really? Never heard of fungus gnats. How would I check for them?

I have pics up now.

It seem t be N def ....Whats nuts do u use ?
R u in flowering stge?

Yes, Just went into flowering a few days ago. I'm using Plagron Bat mix which has organic nutes in it including bat guano. It is high in nutes, but
not so high in Nitrogen which is a good mix for flowering. My ph is btw 6.5 and 7 so shouldn't be any lockout. I'm not sure how much MG is in Bat Mix
but i would think there would be enough. The mix is supposed to be good for 6 weeks without any extra feeding. Anything i feed them is a week solution through the leaves. Any thoughts will be appreciated.