RO and weird pH readings

[markh30]

I purchased a 5-stage, RO system, which produces about 9 gallons a day (at least I think it does). Before I started using it, my pH readings in the aquarium from regular, dechlorinated tap water would average about 8.2. Ever since I started using the RO system, the pH has bottomed out at 7.8. I keep adding a pH buffer, but that doesn't seem to get the reading to go up. Has anyone else had this problem?

 

[cj10488]

Tap water is mad to have a higher Ph to eat away the calcium deposits in the pipes.. When you run the Tap thru an RO unit it will lower the pH.. I would try and Open a window close by and see if that helps.. Also make sure there is alot of surface movement to inhibit Co2/O2 exchange.. Increasing the surface flow.. Removing the hood if its a glass hood... Opening a window should all help with bringing your pH up.. BTW test towards the time the lights go Out.. your pH will always be lower in the early am.. Mine usually stays between 7.9? and 8.1 since my calcium reactor and before it was 8.0- 8.2 But if I closed a window I could watch the number drop at least .1 depending on how many people were in my house at that Time..

HTH<
James

 

[markh30]

Hmmm, that does make sense. Calcium would build up in the pipes. Unfortunately, I cannot open a window just yet being it's early spring in NY. It's still pretty nippy outside. Anyway, I am curious though... How dangerous is a pH reading of 7.8 to a FO tank?

 

[cj10488]

IMO 7.8 is on the Low side but still safe.. Its the lowest that I would ever let it be.. Most people with Ca Reactor run 7.8-8.0 I would test in the early morning before the lights come on and Late at night just after the lights go off.. Also what Test Kit are you using.. I know Red Sea test kits read low most of the time... Just a thought.. You might also tried testing the water and then opening the window for an hour and test it again and see if it is just Co2 build up in your place..

HTH,
James