Thanks for the advice Herbie...i threw in more fresh water yesterday after you wrote, and noted this morning that the ph stayed steady at just above 5, and the EC is finally inching downwards...will try and get EC down to 2 and bump ph up to 5.5 or so and keep these numbers steady through harvest...thankfully, the plants look absolutely fine so no real worries there (for now!).
best
jash
jashbery Reviewed by jashbery on . Ph goes down as EC goes up? The details - two Oasis feminised plants growing in a NFT system with a 20 litre reservoir, with about 3 weeks flowering left to go before harvest. Now, a technical question - while my plants are looking fine these days, I've noticed that the ph these past four days or so keeps sliding down to around 4 every morning, and my EC meter keeps reading 2.3 or 2.4 despite the fact that I haven't put any nutes in the res in some time. Now, I've been bringing the ph up to around 5.5-5.8 each day by Rating: 5