ppm keeps rising

hey everyone quick question for you all. i am running a hydro set up with rockwool medium, using a drip/bubbler system. am currently half way through bloom cycle. in my res. my ppm keeps rising by 150 units per day. i have been adding fresh water to keep ppm at it's desired level. my question is why do my pla nts keep drinking water, and not drinking up any of the nutes? or so it seems. everything is decently healthy no problems to complain about, but i do not understand why the ppm keeps rising so fast. any input is greatly appreciated. appologies if this question has already been asked/answered. thanks for your time.

-iris

Plants drinking water is a good thing. When they stop drinking is when you have a problem.

The plant drinks water and some PPM's but much more water. That makes your nutes ppm go up. Top off with PH'ed water untill you have replaced your rez. 5 gallon rez 5 gallons top up and it's time to change.

Also about your ppm's. Your plants use nutes but they also give off waste that show up as ppm's. So the ppm's don't change a great deal as long as the rez stays topped up.

tank you loc nar. once again you seem to have all the answers.

much appreciated
-iris