Needs to be something in game, that is easy to find, that tells you how to work Fishing Nets
I have placed I don’t know how many and the all have 10 hour timers. However, each time I return after work there is nothing there and it just lets me place another net…
Yea I don’t how these things work either. I placed a net. Went back the next day and…nothing. 
Yeah I have no clue how they work I just stopped using them after the 4th one was nothing but time wasted. 0 reward just a 10 hour timer for nothing.
You are suppose to put a Vulpera in the net, Then throw the net in the water. it needs bait to catch fish, geez…
At least try to learn our dragon ways while your visiting our island.
Apparently there’s a glitch that causes the nets to disappear if you don’t interact with them pretty much immediately once those ten hours are up.
I thought they fixed it, but maybe they’re still working on it.
Luckily, or unluckily, you’re not missing much: you only get around ten fish per net.