First time growing lettuce help needed

First time growing lettuce hydroponically/ever I’m wondering if some of these are bolting or on the verge of bolting? The varieties include buttercrunch, cimmaron Romain, Bibb, red leaf, green leaf, and Boston. The Bibb lettuce is my main concern those are the long skinny looking ones at the top of my system. Didn’t have all the right nutrients which could be part of the issues I was using foxfarm grow big and big bloom so could be low on calcium… checked pH and EC regularly they were in acceptable ranges I did .85-.95 and now I’ve ramped up towards the end here to 1.2-1.8 for EC and 5.8-6.2 on pH. Any advice would be greatly appreciated since I’m getting ready to germinate my next batch