I found a good way to make about 1,000 gold a day afking overnight. Did it for about 2 whole days and had my epic mount on the 3rd day. All you need is a fishbot ( I use pirox fishbot). What your trying to fish for will be Golden Darters. In the past this has been difficult to bot without the fishing gear from stv quest. But now with the new fish quest's you can buy sharpened fishing hooks from the AH for 1g or cheaper for a stack of 20.
Now the best place to fish golden darters is Silmyr Lake or 46,36 ( my favorite spot hidden in the mountains). In about one night of leaving the bot on about 6-7 hours I usually have around 100-120 golden darters.
Tips: Since you will catch feltail's and other fish that are pretty much worthless, the best way to make sure you only put golden darters in your bags is to fish 20 golden darters, then split the stack up into 1 for 20 bag slots. So you have 1 golden darter in 20 bag slots thus forcing the bot to trash any unwanted fish because your inventory is full.
Another tip is with tons of golden darters coming in overnight soon you'll have so many you can easily control the market, which is what I did they were selling for about 20g a stack but only 1-3 stacks were up at a time. So I would buy them out and put 2-4 stacks up for 45g and they would sell with-in 1-4hrs.
And If your scared about being reported for fishbotting I've been playing wow for 2 years and been fishbotting since the beginning have yet to be reported for doing so.