he has been working with the fish for a little while but this new tank might have other fish or he might eep the koi in another place for the winter but my I don't know which filter system to recommend to him my thoughts were something like a rena but i have not alot of info on them and Bev no i do mind you being blunt
no harm. I just put this post to others that are more experienced. my friend had a small aquaclear ?? and i was unsure if there were still effecient in larger setups