Hello everyone, I would like to ask for your help. I have some experiences with aquarium aquaponic (approx 100 l system), but this is something else and I would like to consult this with the skilled users. It is necessary to use swirl filter in the setup I describe below? Buddy has a pond on backyard since June 2018, he's got trouts there and some perches there. The volume of the pond is approx 30,000 liters and is placed in shadow. He use pond filter GREEN RESET 100L (2x25W UV-C, 100 l volume, 16 000 l/h). We got the idea to make the aquaponic system and connect it to the pond by another pump. The AP system includes grow bed (750 liters of gravel) and raft (400 l volume). I design the system with swirl filter unit, but I would like to ask you if this is unnecessary. The raft should be clean, because the grow bed also works as a mechanical filter. But what growbed? Will it be necessary to filter the water from the mechanical particles from the pond? Should we add a worms, which could reduce detritus, but will it be enough in the outdoor environment? Swirl filter serve as "waterworks", where I can reduce all flows and shut down both grow units independently. When we make it withoutthree blue swirl filters it will be simpler and cheaper, but in grow bed will not be filtered water. How would you do that? Thanks a lot for the reaction, I hope I wrote all the information about the problem I apologize for my English and thank you for your help and your opinions.