American Flag Fish Winter

[Sgooosh]

Hi! I recently acquired some of these fish, and they’re currently in an unheated tank with some wild guppies. I’d like to move them outdoors, but it is too cold currently, so I hope to do so next year.
I’d like to move them in with my other fish in my 75gallon, however I add heat to that tank in winter. I’m wondering if it will be okay for the flag fish?

 

[Archerfish]

If properly acclimated, they will do fine. What other fish are in the tank? How many flag fish do you have? I kept them for about 15 years off an on and found them to be very peaceful unless they breed. In that case, the male will aggressively guard the area for awhile, perhaps a few days. They do not protect the brood in my experience, just the eggs. Consider keeping them in a species tank when indoors. Edit here: Please quarantine those fish before moving them into your aquarium! Can't believe I missed that. Wow, early in the morning.

 

[GaryE]

Watch the weather reports for Orlando (to pick a habitat region at random). That will give you the temperature range for future outdoors keeping.

I seem to remember you in California, right? Your location is pretty vague to comment on temperature ranges! As well what does 'heated' mean? I have had tanks heated to stay at 72f, and others for 80f. I expect they'd adjust, but they might like the lower range.