Temperature hysteresis

[dmoraski]

Just curious, what kind of temperature hysteresis do you allow in your tank for heating / cooling?

I'm seeing my tank dip in temperature overnight with the cold we are having in Chicago, so I've had to put a heater on. My Apex is controlling it, and I have it set for a 1 degree hysteresis. From looking at the data, I think I can cut that down a lot which will turn the heater off and on more frequently, but keep the tank more stable.

What do your inhabitants tolerate?

[BlackTip]

My controller and heaters are configured to keep the temp within .7 degree. 77.6 - 78.3

[JWClark]

Wow, I always kept mine between 0.2 on my 125--79.9 to 80.1, controlled by APEX. Had to add a second heater when I switched to LEDs. Will probably do the same with the current build but using MH lighting so we'll see.

[dmoraski]

Thanks. What do you do in the summer, run a chiller?

[tzylak]

Just for the record, hysteresis is the difference (lag) between actual temperature and the one indicated.
Amplitude, or temperature oscillation (between day and night) when controlled, should be no more than two degrees. Uncontrolled swings can be 3-4 degrees and the gradual (12 hour) change should not affect the fish in any way.
From what I see the fish and reef can periodically handle the extremes of 72-82F.

[slief]

Back in 2010, I began letting my tank run it's own course from winter to summer which was a great thing for me as it's saved me thousands of dollars in wasted electricity. In the winter it drops as low as 76* but is usually around 77 and in the summer it maxes out at 82*. I have fans that kick on above the tank to keep it at a max of 82 during the summer even though it really wouldn't go much past that. I don't run my air much in the summer which is the only reason why my tank gets that warm. My pumps run cool as do my LED's. My fish and corals don't seem to mind it one bit either. They actually thrive which isn't really surprising considering many of the reefs where our corals and fish originate from are often higher than 82 in the summer months.

[ca1ore]

What works in Simi Valley may not work in Naperville .... and it definitely doesn't work in CT. I keep my house at 67/64 day-night in the Winter and 78/75 day-night in the Summer. Far too much swing to be a good thing. I no longer run a chiller, so the tank will get up as high as 82 degrees on occasion in the Summer; 78/79 the rest of the year.

[slief]

Originally Posted by ca1ore

What works in Simi Valley may not work in Naperville .... and it definitely doesn't work in CT. I keep my house at 67/64 day-night in the Winter and 78/75 day-night in the Summer. Far too much swing to be a good thing. I no longer run a chiller, so the tank will get up as high as 82 degrees on occasion in the Summer; 78/79 the rest of the year.

Totally agree.. I'm blessed with mild weather here in So. Cal. Now if I ever move to Montana like I would like, I will certainly need to consider different pumps or a heater..

[jason2459]

Originally Posted by slief

Totally agree.. I'm blessed with mild weather here in So. Cal. Now if I ever move to Montana like I would like, I will certainly need to consider being checked out for mental health issues..

fixed ^

I have fallen in love with the Apex Seasonal chart and base everything that turns on and off, intensities, direction, etc, including temp on that. So, right now my tank is around 76*F

[slief]

Originally Posted by jason2459

fixed ^

I have fallen in love with the Apex Seasonal chart and base everything that turns on and off, intensities, direction, etc, including temp on that. So, right now my tank is around 76*F

LMAO! I love western Montana. I lived there for over a year back in the mid 80's and go back whenever I can. I want a river in back yard, trees that I didn't have to plant, maybe a couple horses and a lifestyle that I'm not a slave for. Moving the tank and livestock will be a nightmare but I'm good at planning so that won't be that difficult.

[sixpackgarage]

.2 to .3 degree. controlled by my Apex

[vette.tech]

Originally Posted by jason2459

fixed ^

I have fallen in love with the Apex Seasonal chart and base everything that turns on and off, intensities, direction, etc, including temp on that. So, right now my tank is around 76*F

LOLOL I was thinking the same thing when I read that!!

Weird cause I was actually thinking about this today but didn't make a post so glad that one was made, but fwiw my controller keeps mine at at ~1 degree swing, not including hysteresis

[Jay Fortay]

Went from So Fla to SW Montana. Lots to love here. Lots to miss about FL too (mainly saltwater).

[JWClark]

Originally Posted by dmoraski

Thanks. What do you do in the summer, run a chiller?

Don't know yet, will have to see. Looking for a 1/10HP right now just in case.

Lights are Sfiligoi XR6s and are about a foot above the waterline and open--no canopy. Ballasts are icecaps on the ground so we'll see how it goes. We do keep our house at 78 in the summer and w/ ATI T-5s on the 125 I was struggling to keep the tank below 82--but I had skimmer and return pumps that made much more heat than what will be in this tank.

[Mrs. Music]

Originally Posted by slief

Back in 2010, I began letting my tank run it's own course from winter to summer which was a great thing for me as it's saved me thousands of dollars in wasted electricity. In the winter it drops as low as 76* but is usually around 77 and in the summer it maxes out at 82*. I have fans that kick on above the tank to keep it at a max of 82 during the summer even though it really wouldn't go much past that. I don't run my air much in the summer which is the only reason why my tank gets that warm. My pumps run cool as do my LED's. My fish and corals don't seem to mind it one bit either. They actually thrive which isn't really surprising considering many of the reefs where our corals and fish originate from are often higher than 82 in the summer months.

I am so glad to see this. I forgot one of my heaters broke this summer and I never replaced it. Winter finally hit here in Ohio and my temp dropped to 76.9. I added my little Sera heater and I am at about 77. something at the warmest. I have noticed the temp changes by a degree between day and night over the last couple cold nights. I am worried about that little Sera running nonstop and damaging it. Perhaps it is not worth it?

[tmc1313]

My tank fluctuates between 78-80. My chiller is set at 78, but doesn't kick on until it hits 80 to cool it back down. Seems like a big swing I guess, but it's never been an issue as far as I can tell.

[Scorpius]

As long as you're between 76-82 you're golden. Key is to find what temperature works for your tank and then keep it stable. Stability is the key to success.

My tank runs between 79-80.

[slief]

Originally Posted by Mrs. Music

I am so glad to see this. I forgot one of my heaters broke this summer and I never replaced it. Winter finally hit here in Ohio and my temp dropped to 76.9. I added my little Sera heater and I am at about 77. something at the warmest. I have noticed the temp changes by a degree between day and night over the last couple cold nights. I am worried about that little Sera running nonstop and damaging it. Perhaps it is not worth it?

I am not sure how worth it the heater is. Running a heater 24/7 is never a good thing if they aren't cycling off. That will usually lead to premature failure of the heater and some heater failures can be catastrophic if they burn up or crack. As for the tank hitting 76.9, in my experience, that isn't an issue at all. The key is to not have fast temp swings. Because of my water volume, my tank never changes more than 1 degree in a 24 hour period. Rises and falls in temp are always slow in my system. If anything, that would be my biggest concern. Even a temp of 75 isn't a real problem. I wouldn't want to go lower than that but at 76-77, you are fine and have nothing to worry about.