Reef Angel Forum

I got the salinity attachment for my RA+ unit about 2 weeks ago. The problem I'm having with it is that almost as soon as I'm done calibrating it the reading starts dropping and continues to drop, could this be a bad probe? I've tried calibrating it to regular salt water mixed to 35ppt, and then last week I bought the little bottle of solution and recalibrate it to 35ppt. Now a week later it's all the way down to 23.6ppt. Any ideas?

Probably bubbles or temp swings.
Try moving to a spot without bubbles.

Take a look at your portal web chart...look something like this?



Mine has been doing this since I got it and I cannot figure it out. Many have blamed it on stray voltage but I've added grounding probes, even unplugged everything for a while on a rebuild and no better. I've changed out the probe, moved it around, to no avail.

Let me know if you figure anything out.

Took the probe out of the sump, shook the water off, and put it back in. It went right back to 35ppt, but then immediately started dropping again. It's not a fast drop, maybe .2-.3 per hour, but fast enough that it's concerning.

What happens if you place the probe in a cup with tank water?

Got home from work today and it was back down to 23.9

I just put it in a cup of tank water, it went back up to 35. I'll update you on what it's reading tomorrow, usually drops slowly over the course of a day.

Still dropped, but not as much. In the glass of tank water it made it down to around 32 after 2 days.

That difference is probably due to temperature difference.
It is very difficult to see what is happening because we don't have log of your controller in the portal.

My graphs looked almost identical to the one above when I first got it and I moved it to the other side of my sump and it works smoothly. I think it was collecting air bubbles in the first position.

-Jon