Cats for Hard, Alkaline Water?

[Narelle]

I talk fish a lot with a group online that gets a lot of new hobbyists. I'm fairly well known for my love of catfish, and with recent discussions about only keeping fish if you can provide a tank within their water parameter range, I've been asked a lot for suggestions of cats that are naturally found in hard, alkaline water. But I'm not coming up with much.

Does anyone know of any catfish species that are naturally found in hard, alkaline water?

Preferably only reasonably sized fish (under 8" maybe?) - a list of monsters wouldn't really do me any good.
I'm also more looking for fish that naturally range into those conditions than those who have been bred in harder, more alkaline water and are thought to be more tolerant of it.

All I've found to suggest so far are Rift lake species (basically the spotted synos, as I think they're probably the only ones potentially common enough to find) and maybe some madtom species? (

N. leptacanthus

is found in the area of FL that I'm from, we have a lot of limestone and it gets very warm so I feel like they would tolerate harder, warmer water than most.)

[Bas Pels]

Generally speaking, larger fish are often beter suited for hard water - water rains down, and if it is a tropical forest, it will become soft and acidic. But when it flows away, it can come into contact with minerals. In many cases large rivers have much harder water than the subbranches

My first idea was to keep native USA fish. Any cat among them will be able to be kept in USA water

Further, Central America has hard water, but very few catfish. It´s cichlids and lifebearers which come from there.

Australia might have catfish adapted to hard water, most Australian fish are. But I´m not certain many catfish come from Australia either

last option, Africa outside the tropics - for instance any Syno form the nile might be capable of coping with hard water

[TwoTankAmin]

Have a read here: Catfishes From The Rift Lakes Of Africa
https://www.planetcatfish.com/shaneswor ... icle_id=95