This ph reading cant be right ? 6.75 ?

For over a 4 months now my RKL ph probe has been reading max of 6.75 even if lights have been on all day, dips slightly at night..now I have tried to recalibrate it a couple of times and it always reads good in the solutions( made sure they were up to date and a near tank temp), but it always comes back to that 6.75 ish range never ever even breaks 7 in my tank..so I used a sea chem ph test kit and it came back at 8.3 which makes more sense seeing my ALK is at 10.1 (hanna) and 9 ish with sea chem..my corals and fish have shown no ill signs and have continued to grow nicely..so do you think it could be the probe it self that needs to be replaced ?, how long to they last ?,I`ve had it for approx 3 yrs..TIA.

 

Can't advise on the probe as I've never owned one, but here's a bump for your thread.

Personally, I'd think that's the problem, seeing that your livestock is fine and a test kit shows pH to be normal.

 

I think I read somewhere that the probes are only good for about a year. You need to keep them free of calcium build up also.

 

Now, I'll get ready to duck - but personally I don't test PH. I think that alk, calc, and mag as well as NO3 and Phophate (I forget is that NO4?) anyway - probably hard to trust advice after that question but.....are really the important values in this hobby. If your alk is stable and in a good range, your tank looks healthy, livestock is thriving, there is not a reason to be concerned about PH. Now, if something starts to go wrong in your tank and all of these levels are good, then maybe look at PH as a variable....that's just my advice - probably others will disagree - just don't slam my advice too hard!

 

I test pH just so I can monitor whats going on but there is not much you can do about it if its off without constant swings. Never used a probe before and test kits are known for inaccuracy and difficulty differentiating between colors

 

I had the same thing happen recently, readings in the low six range. If I pull the probe out of the water, the reading doesn't change much, so the probe is bad.

Unless you have a probe with a way to log the data, periodic testing doesn't help much. You need to be able to see the range in values and the swing over time. Once you do have a controller, though, it's apparent why tracking it is important.

 

Buy a different probe,i found mine was giving me readings under 7 as well.Was told by someone to not chase the PH,but i have a monitor and want to know.Mine was about 3 yrs old as well,bought a new one and i'm always above 8

 

Thanks all for the feed back great info. I've never been a chasing number kind of guy I usually go by how things looked in the tank. My elegance tells me when alk may be dipping and one of my month caps lets me know when cal is dropping ( i smart corals lol ). But I was just wondering why I was getting that reading. Had a feeling those probes don't last forever. Does anyone know if the BRS ph probe would work with the RKL. It would be great if it did since im in the group buy. Thanks.

 

What's the best way to safely clean them.

 

If I had the net module on my RKL I could but without it all it gives me is just an average high & low. Only reason I was concerned was when I had my cal reactor hooked up and was running bio pellets but both of those have been off line now for some time. Tank is def better off without those dang pellets (but that's another topic). But like everyone says stability is key.