Growth technology coco bloom ph

is this company ionic bloom ph perfect 5.8-6.0 per 7ml per liter? Can’t seem to work it out online I was told it was I put my new pen in my feed and it says 5.0 with just the ionic in with everything else added in it was 5.5 I am worried now about my plants health with it not being 5.8 minimum but
I’m not sure if my ph pen isn’t accurate as I can’t see any deficiency’s other than bud development is slower than usual I am gutted I’m 4 n half weeks in so hopefully can correct this in the next 4.5 weeks left

What's your runoff pH? 5.5 may be optimal depending on your runoff. I do 5.3-5.5 currently in flower and my runoff comes out 6.1-6.3.