yep, modified net. if you have super spooky fish leave it in the tank for a few hours to investigate. i did this with a very spooky fire eel.. he swam right in and i was able to carefully snug him up and out without mishap. he was 20" at the time. Ive moved 30" arrows with this method as well. and tons of adult oscars. key is once they are in to snug them up so they cant flail around and hurt themselves or you. I would not use this method to move an rtc or anything with spines as they can get caught in the cotton... those are best if you can get them calm to cover their eyes with a towel and hold them with their spines locked against their bodies. Ive used this method in removing large plecos and cats very well, it can just take some patience. and depending how big an extra set of hands. Big cats also may be moved easiest with large slings ( ie similar to whats used in moving sharks and dolphins but smaller/ sized to your fish.)