DAY 66 — Over the weekend I noticed the water temps in the inverts QT rising higher and higher. Concerned, I set out to determine what was going on. I do very little to this tank and haven't messed with the heater since setting it up, so calibration seemed out the window. I turned my focus to the thermometer. It could be that the probe had slime/algae growing on it which was causing a faulty reading. Or it could be that the thermometer needed new batteries. The worst case scenario would be that the heater itself broke and I'd need to get a new one asap.
About a day later I noticed the water temps in my fish QT begin to elevate as well. It seemed unlikely that both heaters (Eheim Jager 50W) would crap out on me at the exact same time. It also seemed unlikely that both thermometers' (Zacro LCD Digital) batteries would go bust at the exact same time too. So I decided to start with the probes.
I took the probe out of the inverts QT, cleaned it off and then let it hang in the open air for a bit. I knew the temp of the room, so I figured if it is reading things accurately it should reflect the actual room temp. And sure enough it did. Since the probe didn't appear to be the issue, I adjusted the heater to compensate for the overheating.
Today the fish QT got out of hand. Every time I'd walk by temps were 79°, 80°, 81°, 82°. what the heck. I even unplugged the heater to see if the water would cool down. Nope, kept getting warmer. Bad powerhead motor? Unplugged. Nope. Finally fed up, I decided to replace the batteries and see if that helped. These thermometers are only 2 months old, so I figured the batteries would still be good. Popped in a new one and my temps instantly read 77.5°.
Now I turned my attention back to the inverts QT, whose thermometer was still high. However, replacing that battery brought on a new worry. It was cold! Like 74° and falling. I quickly realized my error from the day before. I turned the heater down 4° thinking it was too high. But in reality it was set just fine as I'd always had it and my adjustment made the water colder. A quick readjustment to the temp setting and the heater kicked back on. We're on our way back to normal temps again.
All of this is to say if you have anything that runs on batteries, have extra batteries on hand and swap those out first when troubleshooting. It seems that with these Zacro thermometers, they start to error high and then really high when they run out of juice. I don't recall there being a low battery indicator, so this is really your only warning. If you take these low battery readings literally you could end up making heater adjustments that cause dire consequences. Fortunately I think I caught mine before any sustained cold/hot temps could cause any problems.
Another idea is just to go with stick-on, mercury-like thermometers that don't need batteries. Although I do not know if they are as accurate or as easy to read than a digital.
And finally, heaters do break.
BRS has good advice to just replace your heaters every year by default. But it'd also be wise to have backups on hand just in case something goes faulty prior to your yearly replacement. I do have 1 backup that I use to heat my mixing water. So I could have leaned on it in a pinch here. But that's just 1. If the heaters in both QTs failed at the same time I would have been SOL and found myself running up to the LFS or Petco to get something cheap.
In other news, I woke up in the middle of the night realizing that I, once again, forgot to remove the carbon from the filter when dosing GC #2 last night. Ugggggggggggh. I removed it first thing this morning. At worst it was in there for 10-12 hours. I'm not doing anything to adjust for this. Not redosing now. Not waiting days to redose again. I'm done with it for now.
The clowns are due to come out first. They show no issues related to what GC treats anyway. I figure I move forward with getting them out of QT this week and keep an eye on the other inhabitants. If they start showing signs of flukes then I'll consider another dose of GC at that point. Otherwise we're focusing on transitioning to the DT!