So i am assuming you are refering to sunfish as in the native species of sunfish that are commonly found in local waters? If so a couple things u may want to keep in mind before u go all out setting up a tank just for these lovely creatures.
1. Make sure your state doesnt inhibit the average everyday run of the mill hobbyist from keeping wild fish as pets ( I know it may sound crazy but some states have such laws...lol.... not that it really matters cuz i would keep em anyway if i wanted too).
2. I have actually kept bluegill and warmouth sunfish together in a 55 gallon along with one small yellow perch but the thing that u have to remember is that once u take a wild fish from its natuarl habitat and you try to return it to the wild its chances for survival decrease greatly. So in saying all that research your fish very well some sunfish are very territorial as cichlids are and aggresion levels may run high. Also it goes without saying but make sure ur fish wont outgrow the home u have provided for them. The bluegill and the warmouth that i kept both reached about 5-6" roughly before thier demise which was about 2 years in captivity(this probably would have been longer but we had a power outage and i was on vacation so i came home to dead fish).
3. It is also very important to get your fish very small so u can train them to eat prepared foods because its a real hard thing to find natural foods year round in alot of places in the country. Plus you also need to research as much as u can about thier specific diet needs because most prepared foods are centered around tropical aquaria and those diets differ greatly from these fish which u plan on keeping.
4. On the brighter side of things you wont need to worry about a heater unless u plan on keeping ur tank outside...lol....but heavy filtration is a must as these guys are very very messy(take and adult oscar and multiply that by about 5...lol). So regular water changes are a must. They wont fare well with tropical species because they will eat anything that looks like food it may work for awhile but trust me they will terrorize anything u put with em.
Well eough rambling on from me i think you probably get the point i think native species can make wonderful pets especially sunfish but like with any other fish u gotta put in the legwork so to speak.
