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nano hydor theo - controller or replace altogether?

587 Views 6 Replies 4 Participants Last post by  angyles
I currently have 2 hydor theos in my 2.5 and 6g tanks and both heat the water to 78F, even though I have them turned to the lowest (68) setting. I guess my first question is, has anyone else had this experience?

I'm considering buying a separate heater controller to help compensate for this. Does anyone have any thoughts or experience with that?
My 2nd question is, what would be a good alternative? In my 6g edge, I have carbon rili shrimp and boraras maculatus. While the fish are okay at 78, it makes me nervous to keep the shrimp there long term. I've noticed they're a lot more active which makes me think they're stressed. I would much rather keep it all around 75.

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I dont know for sure but my 25w hydor is at 78 when the dial says 71. Looking at the knob it looks like it might pull off or something to calibrate it. Ive haven't messed with it just because it hasn't bothered me in 2 years. But maybe someone else will know or you could call hydor.
The numbers on heaters are generally very "questionable"? I never expect them to be accurate until proven. But if you have them turned down fully, you may need to check further as heaters, especially the cheaper ones, have a terrible problem of sticking in the on position. It often has to do with the contacts welding themselves together so that they don't open. With a bit of caution, one can reach in and feel for heat. Caution so that you don't hold it too long or too tight and get a burn? If you check it several times and it is hot each time, one can assume it has failed even though any LED or light may not tell you the same.
If they are staying on all the time, I replace them.
But I also now use a temperature controller on all my heaters on tanks with fish. I've lost too many fish and it is way too much stress for me to deal with it ever again when a controller can prevent it. I find the Inkbird controllers are an excellent controller if you are not into doing the work to DIY a setup using one of the cheaper digital controllers that sell for less.

There are several options but this is a review of one that I really like:
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it's not running constantly, I do see it turn off all the time. It more seems a matter of it's thermostat being significantly out of calibration. I also have to mention these 2 thermometers, while the same model, were purchased a good 3 years apart. It seems this may just be the nature of this heater, which has always been fine for a betta, but not shrimp.

I went ahead and ordered a controller. seems like that might just be the best bet. I looked at terrarium heaters but that seemed like too much of a wild card too. hopefully the rasboras can handle 68 until it arrives Friday!

Now I have to decide if I want to use it with the 25W theo, or the little 10W 78F preset heater I have. I'm leaning towards the little guy since he'll take up less room and if there is ever a malfunction, it's less W.
They're junk. I bought from Foster & Smith and had the same problem. Left a bad review and emailed the company, they ended up sending me replacements for all the ones I'd purchased. They were exactly the same. Best thing to do if you're not going to replace them is remove the boot around the knob. You can then turn the heater down lower. Keep going down until you reach the tank temp you want. That's what I had to do and sometimes it's still questionable. They're just junk.
Now I have to decide if I want to use it with the 25W theo, or the little 10W 78F preset heater I have. I'm leaning towards the little guy since he'll take up less room and if there is ever a malfunction, it's less W.

This was the point which final pushed me over into the controllers!
I had a group of 37 bristlenose to take to auction the next morning so moved them to a ten for just overnight. I never like snagging fish at 6AM so want it as simple as possible!
But then I found a 50 watt Theo can fail and cook all your fish in less than six hours! I found 25 watt was not enough but 50 was way too big and dangerous without some backup protection.
I do not feel they are a good heater and they do fail often but then I have not really found a heater to like in the small sizes!
oh man that's terrible :-( I had a 25W cook a betta once. Since then, I always try to undersize my heaters and go with the minimum possible to maintain a safe temp, so if it's stuck 'on' the fish don't cook. Or on a very big tank, split it between 2 small heaters. But like you said, with a small tank it's pretty much impossible. There are no good options it seems.

I cancelled my original order for the Finnex controller and ordered the Inkbird you recommended. much better reviews. I'm thinking I'll hook it up to the little preset 10W heater and hopefully have a perfect 75F tank!
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