Thermometer Knife in a preditor community?

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Prinxe

Feeder Fish
MFK Member
Jun 15, 2024
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Recently my LFS got a couple Thermometer Knifefish in and they seem so cool but I can barely find any information on them. Does anyone know if one would work in my tank?

I've got a Senagal Bichir (P. Senegalus) that's about 5in or so
A Reticulated Bichir (P. Mokelembembe) of the same size
An old Peacock Cichlid Hybrid
A Common Pleco
And a Red Tailed Shark

Its a 55g planted tank with sand that's gonna get an upgrade to a massive tank in 2025/2026 but for now is effectively a grow out for my bichirs who are still both under 2 years old.

So if anyone has info on them I'll take it. Like do they prefer to live with other Thermometer Knifes or are they territorial? Even if I don't get one now, I'll likely look into it again in a year or two so if they won't work in my current tank I still want to learn more about them.
 
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Agreed, not much out there on thermometer knives, or on here either if you search for them.
Like many specialist knifes I would expect them to be territorial with their own kind although this is a species I have not kept.
12” so not out of sync with your two polypterus. My concern would be with your hybrid cichlid as the knife will spend more time “moving” and “off the bottom” than the birchir do so may make him a target for any aggression. Albeit, appears to be a knife that loves burying in sand.
Appear to be fairly “easy going” with water parameters so go on typical for knives from Amazon/ Peru. Water temp of mid to late 70s seems common. Ph around neutral.
Folks seem to suggest it’s a little hardier than it looks too.
 
Agreed, not much out there on thermometer knives, or on here either if you search for them.
Like many specialist knifes I would expect them to be territorial with their own kind although this is a species I have not kept.
12” so not out of sync with your two polypterus. My concern would be with your hybrid cichlid as the knife will spend more time “moving” and “off the bottom” than the birchir do so may make him a target for any aggression. Albeit, appears to be a knife that loves burying in sand.
Appear to be fairly “easy going” with water parameters so go on typical for knives from Amazon/ Peru. Water temp of mid to late 70s seems common. Ph around neutral.
Folks seem to suggest it’s a little hardier than it looks too.
I find my Polypterus spend a good amount of time swimming around on l levels of the tank and my cichlid seems perfectly fine with them after an adjustment period. No one really bothers her and she shares territory alright. She’s still a cichlid so she’s got a mean streak but eventually backs off. So I’d wonder how she’d do with a knife.
 
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