Two things -

Check the local laws. Sometimes there are legal issues with taking native fish. Conservation and fishing laws that I’m sure you know something about being a fisherman.

Research the Fish. There are probably many local fish you can keep, but some will grow too big, some have special diet needs etc.

I and some local friends are keeping some NZ native coldwater fish. Fascinating fish and never seen in the global fish trade, probably totally unknown outside NZ. Some issues are water temp and feeding. Now it’s summer I’m having to put bottles of ice into the tanks to keep the temp down and some only eat fresh or live food.

Ian

There are some quite strict legalities involved in taken wild fish out of rivers and lakes and plonking them in a fish tank. Many species may well be protected and you don’t want to go breaking the law!

British fish are all temperate species and will not survive in warmer tanks. They have fairly short lifespans in average home aquariums. Small fish like Sticklebacks for instance are very difficult and many starve and refuse to eat.

Although these are farm raised they are out it the wild too; my school raise rainbow trout and channel cat fish in our FFA aquaculture class. There are about 40 fish in a single tank but they are about 800 gal. tanks, so I suppose it depends on how much room you have to own a very large tank(not aquarium)

First, make sure you are allowed to do this. If your not allowed to do it and want to do it any way, don’t get cut
I went to ask about this a year ago after a client asked me for a tank with wild species. The guys at the government could not find any law about this. So what they told me is that the fish in the tank will be part of my catch limit.
For that reason, we tried to avoid species we like to catch such as lake trout, pickrell and white fish.

The best species we found was siscos.

When setting up your tank, think about the following:
1) The size of the fish
2) The water temperature. Here in canada, most fish will require a chiller to keep the water cold enough

Good luck