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Your Damsel troubles are over!!

Jan 3, 2007
Have you ever tried to catch a particularly feisty or diseased fish in an aquarium that is heavily planted or full of delicate live rock? This simple, but clever fish trap will help you catch a delicate or sick fish with no damage to aquarium or the fish itself.


A 2-liter bottle. Pepsi seems to work best.

A tool to cut the 2-liter bottle

A tool to punch holes in the bottle

Zip ties. You should avoid “twisty ties” because the have metal cores.

A bit of fish food that is highly favored by the fish you are attempting to capture


Start by cutting the top 4.5 inches off of the 2-liter bottle.
Cut the screw top off the bottle to make a large enough opening for your fish to swim into.

The top part should now form a funnel. Invert this funnel and insert it into the bottom portion of the bottle. Punch some holes to hold the bottle pieces together and secure with zip ties.

The DIY fish trap construction is now complete.

Setting the fish trap

Place some food in the fish trap, and submerge it in your aquarium. If you need to sink the fish trap to the bottom, you can put a little aquarium gravel from the tank inside the trap. Just leave the fish trap in the aquarium until the fish you want to catch swims right in!


I made one of these and it worked GREAT!!!
I saved myself from buying the one I found online for $35.
A word of caution. Many compounds adsorb to plastic soft drink bottles and even boiling them can leave chemicals on the surface that can be slowly released into your tank. I've lost both octopus and and stomatopods trying to ship them in bottles that I had washed and boiled for several minutes. Admittedly, concentrations will be much higher in a bottle a quarter full of water for 8 hours, but some chemical will leach into a your system.

On the other hand, I routinely use spring water bottles and I have never had a problem. I think it advisable to play it safe and stay away from plastic bottles that held anything other than water.

It is only the sort of thing you think about sitting in an airport in Tahiti in the middle of the night waiting for an 8 hour flight home with all of the octopus and stomatopods you caught over the past two weeks dropping like flies because you put them in plastic coke bottles.


Excellent timing!

Thanks for the DIY trap, I will try it this weekend as I have two fish I want to move from one tank to another and the three of us have not even come close to catching these over the last two months!

I'll thaw out one of my frozen, chiller/air conditioning failure water bottles to try it as I have put these to use several times without loss of fish. Thanks!
Sadly, my Chromis won't go near it. I did catch 5 snails and an urchin but the Chromis just wiggled 8" away and kept waiting for their dinner. I thought about a larger bottle but I have a clear plastic net with a MUCH wider opening (purchased for this purpose) that they avoid in the same irritating way.

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