I grow with bio buzz nutes allmix, soli.. iv had some problems 2 week into flower .. its a well known fact it laks mg that's why you getting problems .. iv tried a dose of Epsom salts didn't really do any think .. uped the grow in fower it slowed it down but still problems.
Now personaly I don't feed at all in veg because that will lead to lock out problems in flower...
I add half a ml / l of grow half ml / l bloom .. 1 st week I'm on my 2 nd week now . 1ml bloom but stick with 1 ltr grow till fnal week..
I was having problems .. but no any more my plants have not 1 yellow leaf any were last few grows ..
You need to exspirement . Get ut to wat ur plants need ...
Peace