Use this foam! I don't know if I could ever find anything that would come even close to working like this did... :) I will post a video of it working and catching fish and peppermints very soon..
Coming to this one late, so this is for anyone who lands here with the same problem. The trap advice above is sound — I've used plenty of them — but the part nobody warns you about is the wait. Most need several days before the fish is comfortable enough to go in, and someone in this thread spent three months before giving up and pulling the rock apart. When you're trying to get an aggressive fish out before it does real damage, days matter.
Full disclosure — I'm the founder of FITC Aquatics. That exact waiting problem is why we put together a guide comparing how fast each catching method actually works — useful context if days matter, like they clearly did here. AquaCove gets a mention as one of the faster options.
