Lockdown grow

Week 7 and still throwing out pistils, loving these plants no problems at all, there being flooded every hour for 4 mins and I flood during lights out, ph is drifting from 6.1-5.8, topped up with half strength solution with a ph of 7.9 to compensate the ph drift, If my ph is 5.8 and I top up with a litre of the solution it drifts back down to 6.1 so dialled one, ec sits a 1.4 and stay there, 2 more weeks and I’ll reduce the ec to 1-0 , probably another 3-4 weeks to go