What Temp Is Your Tank?

[stanleo]

I have peppered corys, false julii and sterbiia, harlequin rasporas, pearl gouramis, angelfish, albino Von rio tetras, otos, a clown pleco, and bamboo shrimp and mystery snails. I keep my temp at 79 to 80F degrees. I notice normal behaviors from all the fish. I am wondering if this is too high. Is it is what should it be? I am also wondering what other people keep their tanks at.

 

[Fishmanic]

I keep my tanks with stocking indicated in my sig, at 76 degrees.

 

[techen]

Always do your research on what your fish like in terms of temp. Angels like high temps where corys prefer cooler temps

 

[Lillefishy]

Peppered corys like much cooler temperature than most corys, around 22C, false Julii's also like it cooler around 24C as do Oto's, sterbai can take higher temps.
As Techen said, always research the temperature requirements of the fish you want to stock as one temp will not suit them all

 

[stanleo]

Yeah the reason its so high is when I first introduced the fish I put one in one with fin rot that quickly spread so I raised the temp of the tank to 80 while I was treating for it. Then when I was done I figured the fish seemed to be so healthy and the one cory that was losing fin was getting some back so I left it in that range. I will lower it to 77F as that is the high for peppered and false julii corys but not too low for the angel. Thanks.

 

[Byron]

Here I would lower the temperature to 76/77F.  I find that in most cases, this temperature works for similar mixes of fish species.  Now, there are exceptions.
 
Angelfish were mentioned as needing warmer temperatures.  This is true for wild caught fish which, like discus, require above 80F.  But commercially raised fish do not, and around 77F will be fine [I'm assuming you do not have imported wild angels].  
 
The corys are OK with low to mid-70's but 77F will not be stressful.  I have many species of almost exclusively wild-caught corys and they are all at 76/77F and spawning regularly and living long, so this seems to work.  Some species can manage fine at warmer temperatures, like C. sterbai mentioned, and this is why they work so well with discus.  But my wild C. sterbai have lived for years and gone through the spawning process in my 76/77F 115g.
 
There are species requiring higher temperatures that would have difficulty in the mid-70's but not those mentioned in your post.  
 
Most reliable sources will give temperature ranges for a species, and one needs to remember that unless specified otherwise, the lower and upper end of the range is what the fish can manage short-term, but the mid-range is the long-term temperature.  The higher the temperature, the more energy the fish uses just to maintain its internal homeostasis, which is the various processes that keep the pH of its blood steady, strengthens the immune system, provides good digestion, blood circulation, and so forth.  Making the fish work harder at doing these essential things is going to wear them out.  Think of how you tire more when exercising in hot weather; same principle, except with the fish this is literally burning them out because the temperature remains where we set it so there is no respite, and they do not have the ability to regulate their internal temperature.  
 
In the wild, water temperatures usually vary with the depth, overhanging vegetation, stream flow, etc, and fish can move accordingly.  This is not the case in the aquarium.  And most of us maintain the same temperature 24/7, which is certainly not the case anywhere in nature where these fish live.  Some advocate two sets of heaters on timers, one warm for the daylight, the other cooler for the darkness, and there is food for thought in this approach.
 
There is an article on another site that delves into temperature, and the author suggests not heating tanks if the ambient room temperature remains in the low 70's F.  It is an interesting concept.
 
Byron.

 

[stanleo]

You know, I have considered that the temp should lower during the nighttime hours. I have thought about putting the heater on a timer but I decided that it would take too long for the temp to raise during the day. What are your thoughts on that?
 
I turned my old heater off and took it out and in eight hours the temp lowered to only 79.5F down from 80.4. My light was on the whole time. After the lights went off it dropped 0.3 degrees in 1.5 hours. My apartment is kept at 72F. I bought a new heater that is easier to set the temp with. I am going to leave it off all night to see what happens. 
 
My light is more than 6 inches above the water line. How much heat can a T5 HO light let into the tank?

 

[Byron]

Tank lights certainly generate heat.  This is an advantage or the opposite, but if the tank does heat above the heater set temperature, the heater will not come on until the temperature lowers, and the difference caused by most lighting is not great.  The type of lighting is a factor too of course.  LED lighting has the benefit of being very cool by comparison to fluorescent tubes or CFL bulbs.  My dual tube T8 lighting over the 4 and 5-foot tanks doesn't raise the temperature by more than 1 degree F, according to my digital powered thermometers.  When I had T5 for a trial, it did seem warmer.
 
The tank temperature will remain close to the air temperature in the room, ignoring all influences such as lighting over the tank, filters (some suggest they may increase warmth but very little I would think), sunlight if allowed to hit the tank directly (this can really raise the temp fast as glass magnifies the sun's rays), etc.  For example, my fish room in summer gets direct sun all day and the room really heats up, well over 90F.  I have a room air conditioner that keeps the room around 80F (I cannot get it cooler, the sun is so direct) and the tanks will rise to this temperature during the day, then cool down at night.  For relatively short periods during summer this is not an issue.  The point is that the tanks heat or cool to the air temperature, and water takes longer to heat and cool than air.
 
Byron.