Loaches Online Forum

I just thought I'd share an interesting observation I made on the small pictus catfish I'm growing up in my second 473 liter until they get big enough to go into the originally archerfish 473 liter.
Their current water temperature is 20-22 Celsius (seems to vary a bit, IDK why), as opposed to the 24-27 Celsius most fishkeepers keep them at, and they've been that way for over 4 months. But no whitespot, no decrease in activity, and no decrease in appetite either. I'd say if your other fish can also do well at temperatures like that, you should set your pictus catfish tank to that temperature to save on the electricity bill.

This is pretty similar to the observation I made about the black and striped kuhli loaches that are also doing well at these temperatures compared to much higher 'recommended' temperatures.

Pimelodus pictus comes from a huge area, and yes I think the ones from Peru, Colombia wll need lower temperatures then the Brasilian ones, from lowland Amazonia.

Still, I would not have guessed 22 C would suffice. I would have guessed around 25 C

Nice observation!!

Thanks. It does make one wonder what is at play.

My best guess would be that cold water flowing down from the Andes headwaters may be dropping the temperature of lowland water that would otherwise be warm. I've heard from another fishkeeping website that this is the case for the Magdalena - the person who I heard it from swam in the delta of the Magdalena and it was only in the low 20s Celsius despite the air temperature in the area of the delta being consistently much warmer all year.
https://en.wikipedia.org/wiki/Barranquilla#Climate

Come to think of it, I wouldn't be surprised if those pictus catfish were actually from the Magdalena, as I was told the shipment came in from Colombia. Wikipedia has the 4-line pictus catfish/P. blochii listed in fish from the Magdalena too, and that list is 'incomplete', so even though P. pictus is not listed I don't see why it couldn't be present if the 4-line pictus catfish is.

Mountain streams cooling waters of collection points might also be responsible for the kuhli loaches doing well at temperatures that low. I know that the Indo-Malayan region where kuhlis are collected has many cool mountain waters downflowing into tropical lowlands.

That's an interesting observation you made about the pictus catfish and the kuhli loaches thriving at lower temperatures than what is typically recommended. It's great to hear that they are showing no signs of health issues and maintaining their appetite and activity levels. Adjusting the temperature of the pictus catfish tank to save on electricity costs could be a practical consideration if your other fish can also tolerate those temperatures. Thanks for sharing yourImmaculate Grid experience!

Noah1019 wrote: ↑

Mon Nov 27, 2023 1:52 am

That's an interesting observation you made about the pictus catfish and the kuhli loaches thriving at lower temperatures than what is typically recommended. It's great to hear that they are showing no signs of health issues and maintaining their appetite and activity levels. Adjusting the temperature of the pictus catfish tank to save on electricity costs could be a practical consideration if your other fish can also tolerate those temperatures. Thanks for sharing yourImmaculate Grid experience!

You're very welcome! Thank you for sharing your thoughts.

I hope if any other members experiment with lower temperatures for the species in question, they will share results here.