I had read books and websites on how to build a fish trap using soda bottle(s) with many different variations and I had personally tested a few designs and most works but not perfect. I am designing one just for those fishing in canal or just for fun. I will put those designs that does not work that well in a canal and those works.
This design works well in an aquarium tank and you can trap the fish safely without using the fish net and risk stressing out the fishes. However you cannot choose which fish that you want to trap and it does take some time for the fish to find it's way into the bottle by using bait.
This design also not good enough for catching wild fishes in the sea or fresh water fishes as they will swim back out quickly.
I read the book on SAS Survival Guide on the fish trap section did show the above design but I soon realized it's not good enough in catching fishes in the wild. I search deeper into the internet world and found Soda-Bottle-Fish-Trap at instructables.com but it's basically the same concept but with different method of building it.
Here's how I created my version of a relatively cheap fish trap using a bigger plastic bottle and a small stainless steel wire mesh for water drainage.
Firstly, I got a bigger plastic bottle from the supermarket. This is the bigger version then ordinary soda bottles for bigger fishes.
Then I use a scissors to poke an hole and cut around the bottle head, do not spoil the head as you need it for the trap to work.
This looks like the original design but it's not complete yet! There are more things to add to this design to make it more effective to catch fishes in the wild! :)
The idea is to make a water drainage at the bottom side of the fish trap where the head is the inverted bottle neck and the bottom drains the water out when you pull the trap out of the water/Sea.
Cut out the stainless steel wire mesh for washing vegetables and fit the wire mesh inside the bottom of the fish trap and use some fishing lines to tie it up nicely and securely.
Then on the top side use stapler to stapler the fish trap plus drill two small hole to put the fishing line through for holding it upright when lowering down to the water. Put some weight at the bottom to let it sink down faster. Since the water can pass through easily, it will sink like a stone. Put some of your favorite fish bait in and watch the fish go blindly into the trap.
When hoisting up the fish trap, the water goes out from the bottom hence making it light weight and harder for the fish to swim out as the water pressure is pressing downwards while the trap are pulled out of the water.
You will be surprised how easy to catch fish using this. I had tested a smaller version of this with great success. I will test out this later this week and hope to get video for you to see how it works. Pray that it won't rain on Saturday or Sunday! :)
Now you can see more detailed instruction to build this trap at instructables.com
