Is it normal to only drink once a week in mid flower?

Agree the fans for ventilation seem to encourage growth and water evaporates faster.

Do you have good ventilation under the pots? I like to have flow passing under the plants too at the end they slow down on water is there where i like to make all my fans and ventilation full so i help them to dry

If their not drinking much now it may be due to some salt buildup in the soil. If you see any clawing of the leaves or spots coming on, this would verify it. Adding more often would only compound the problem. I would skip a feed and just water. By the end, they drink a lot less, but I find that to be the case, about a week or 2 before their done.