Welcome to R2R!!! I agree that it is great fun and can be very interesting to collect fish and inverts in the wild. I have done a lot of it in freshwater, brackish, and saltwater. I would strongly caution you to not bring home fish that you aren't able to identify for many reasons, but especially because they could be endangered species. There are many reasons that the fish may not have survived including poor water quality, disease, stress, failed transition to new types of feed, and many more. Certainly some species are able to thrive in home aquaria far better than others. There is an organization called the "North American Native Fishes Association" (NANFA) that has a lot of tips on their website about collecting. Additionally, if you can post pictures of specific fish either water side or in your tank and post them for ID or describe and post pictures and water parameters in the fish disease sub-forum you may be able to get more help there as well. We're glad you're here and wish you the best of luck in your adventure!