Temp in Coldwater Tank

[Qsilver7850]

I've got a 40 Gallon Breeder with 12 gold barbs, 3 zebra danios, and 4 white clouds. I've taken out a variety of other fish and rehomed them so I can do a cold water tank. The tank is in my basement and my open top ten gallon shrimp tank nearby gets to about 61-62 degrees.

Is that an okay temperature for the 40 gallon? I've done a bunch of research on the three species that are in there and I get conflicting specifics about the temp.

[Sleepy]

That seems a bit borderline to me at least for long term. If you have a good lid, light and some kind of electrical filtration should raise it up to a more (in my opinion) acceptable range.

[nabokovfan87]

On 2/13/2023 at 1:39 PM, Qsilver7850 said:

The tank is in my basement and my open top ten gallon shrimp tank nearby gets to about 61-62 degrees.

I can point you to some articles and studies.  Shrimp, neos specifically you don't want to get too cold or they will start to have issues stemming from muscle failures.  Essentially, there is a "too cold" and the deaths usually start from the body shutting down, specifically their muscles.

For coldwater tanks I don't go below 68 if I can help it.  For fish I set heaters to 72 (if it drops below that's ok).  I try to keep a floor of temps, so to speak. 

 

[Qsilver7850]

On 2/13/2023 at 2:07 PM, Sleepy said:

That seems a bit borderline to me at least for long term. If you have a good lid, light and some kind of electrical filtration should raise it up to a more (in my opinion) acceptable range.

That's been my thought too, that presumably it will warm up a bit with a lid and the HOB.

 

On 2/13/2023 at 2:13 PM, nabokovfan87 said:

I can point you to some articles and studies.  Shrimp, neos specifically you don't want to get too cold or they will start to have issues stemming from muscle failures.  Essentially, there is a "too cold" and the deaths usually start from the body shutting down, specifically their muscles.

For coldwater tanks I don't go below 68 if I can help it.  For fish I set heaters to 72 (if it drops below that's ok).  I try to keep a floor of temps, so to speak. 

 

Oh really? I thought cherries were good down to the mid-fifties. And I thought 72 was just a general temp for fish. I was reading that white clouds specifically have shortened lifespans if they're kept above 72. I'd be interested in any articles you have to share!

[Colu]

Everything I have read about golden barbs zebra danios and wcmm suggest no going below 64 

[Val]

62 degrees?  That seems awfully cold for cyprinids.  I just reviewed four guides that give temps for fish and the lowest I could find for any cyprinid was 64.  And that wasn't for the danio or the gold barb.  Where are you getting this conflicting info?

 

Edited February 13, 2023 by Val

[nabokovfan87]

This one is worth a read.  It's a master's thesis paper and goes into population control of a native species and how the shrimp are impacting the ecosystem.  Fun read.

https://open.library.ubc.ca/soa/cIRcle/collections/ubctheses/24/items/1.0380902

This one is specifically about breeding colony temp, growth, and how well the shrimp do at certain ranges.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0119468

For reference... 24C = 75F
 

Quote

Growth period
At days 30 and 60 of the Growth period of both experiments body weight was lowest, highest
and intermediate (P < 0.05) in juveniles maintained at 24, 28 and 32°C, respectively. However,
at day 90 this variable was similar (P > 0.05) among treatments (Fig. 3). The growth increment
(GI) was significantly lower (P < 0.05) at 24°C than at the other temperatures tested over the
first 30 days. This was completely reversed during the following 60 days, with the GI of shrimps
at 24°C exceeding that of shrimps at 28 and 32°C (P < 0.05). At the end of the Growth period,

Quote

Interestingly, the GI of shrimps at 28°C was found to decrease from day 30 onward. It is
well known that ovarian maturation and somatic growth are antagonistic processes from an
energetic point of view. The energy costs of ovarian maturation are high due to the increase in
biosynthetic work, which supports the lecithotrophic strategy of the embryos [38]. On this
basis, a possible explanation for the decrease in GI may be that females maintained at 28°C al-
located a greater amount of energy towards reproduction than towards growth compared to
females at 24 and 32°C, as evidenced by the highest proportion of growth-phase ovigerous fe-
males being obtained at 28°C.

 

Here is another, specifically about what they go through at cooler temps.
https://www.frontiersin.org/articles/10.3389/fmars.2021.746177/full

[Qsilver7850]

Thanks nabokovfan, those are some interesting articles.

As Sleepy said, I'm going to see if my equipment keeps the tank at least 64. If not would a 75 watt heater be enough to raise the couple degrees? I'm trying to just use what I have on hand.

Also seems like the shrimp would benefit from a heater but I'm literally out of outlets.

[Biotope Biologist]

I have a 50 gallon “cold water” tank in my living room. Have had temps dip to 63 once or twice but mostly the temperature stays at 65-68 degrees. Interestingly ambient temperature at my house is also in that range. 
 

I keep white clouds, gobies, and a cyprinid called orange fin hill trout. Similar to a danio in nature. They all enjoy that range quite well. I also have shrimp in the 10 gallon sump below. They also are doing well. They have doubled and tripled in size since I got them. A couple females are carrying eggs. 
 

These are the temps that these fish are most likely to see in the wild. I understand basements stay quite a bit cooler than the rest of the house. If you don’t have ways of insulating the basement I’m sure a small water heater could bump the temperature a few degrees.

[AngieVaughn]

On 2/14/2023 at 10:06 AM, Biotope Biologist said:

I have a 50 gallon “cold water” tank in my living room. Have had temps dip to 63 once or twice but mostly the temperature stays at 65-68 degrees. Interestingly ambient temperature at my house is also in that range. 
 

I keep white clouds, gobies, and a cyprinid called orange fin hill trout. Similar to a danio in nature. They all enjoy that range quite well. I also have shrimp in the 10 gallon sump below. They also are doing well. They have doubled and tripled in size since I got them. A couple females are carrying eggs. 
 

These are the temps that these fish are most likely to see in the wild. I understand basements stay quite a bit cooler than the rest of the house. If you don’t have ways of insulating the basement I’m sure a small water heater could bump the temperature a few degrees.

I have similar temps for my 55 in my main living area too. We like a cool house 😁 I have swordtails, platys, mystery snails, and albino corys in there they all do just fine. 

[Qsilver7850]

After leaving it for a few days the temp seems to have stabilized around 64° in the 40 gallon. I might get a heater for it anyway to bump it up to 66° or so.

Also, the shrimp tank is now at 69/70°. I had to run an extension cord from an outlet in the ceiling but it works.

[nabokovfan87]

On 2/13/2023 at 3:04 PM, Qsilver7850 said:

Thanks nabokovfan, those are some interesting articles.

As Sleepy said, I'm going to see if my equipment keeps the tank at least 64. If not would a 75 watt heater be enough to raise the couple degrees? I'm trying to just use what I have on hand.

Also seems like the shrimp would benefit from a heater but I'm literally out of outlets.

My apologies, late to see this.

40G tank. I'd run a 200W heater.  You don't need it on 24/7, but in terms of that volume of water it gives you the most wiggle room and will be off/on pretty quickly.  A 75W should work for a few degress, but it would simply run for longer to do the same job.

You can always try it out, see if it works well enough, or if you're just using too much power to maintain temp.