the ORP, PH and temperature are all sampled when the pump is running, so from 10am to 4pm each day. i capture the 5 minute reading from each sensor then compute a single average for ORP and PH for the given day using this data range. i do that so that i have a useful trend over a period of a week, otherwise the 5 minute average plots i did originally dont really help give an indication on a week view whats going on (up or down). so i favoured a single snapshot of the day, based on this 6 hour 5 minute data capture for ORP and PH.
temperature;
this is solar heated, in melbourne australia during summer - although a slightly cooler summer this year
ORP
you can see initially my ORP was too low and i kept getting sight green algae in the corners of the pool so i had to add more salt, alkaline and ph buffer accordingly to bring it all up to normal levels, around 650ish ORP, i havent seen any algae since hovering around 620+ ORP
Ph
the water here is pretty hard so each time i top up the pool, i need to rebalance and bring ph down. i find the ph constantly creeps up each day slowly over a week when its a hot week and the pool cops lots of afternoon sun. need to balance with stabiliser and ph down to recover
