As all aquarists know, there will come a time when you will have to remove at least one fish from your tank for one reason or another. Whether it's illness, injury, a holding female or just a nasty fish that you want to return to your local fish store, you will find yourself staring blankly at your tank, asking yourself one question... "How the heck am I going to get that fish out of there?".
There are several methods and tricks and I will go over a few of them in this article.
The smaller the tank, the easier it is to corner and net a fish. The less rockwork there is in the tank the better. However if you find yourself trying to catch that one elusive fish in a 55, 75, 125 or 250 gallon tank with more than 100 pounds of rocks, it can seem like a daunting, perhaps impossible feat. So... what is there to do?
The first and most involved process is to remove all the rocks and chase the fish with a net. The bigger the net, the better. It may even work better to use two nets to sandwich the fish between them. This method is always successful but can be very time consuming and very stressful to the other fish in the tank and I use it only as a last resort.
It's always better to try and catch a fish at night. They are lethargic and slow. This makes it easier to scoop up a fish floating in the open. However, it's hard to see and not always successful.
Another method is to put food in a net and coax them to swim into the net. Sometimes leaving the net in the tank for a few hours and then putting in food helps them to get used it being in the tank. This will usually work on most juveniles but I've found the older a fish gets, the smarter he gets and it won't take them long to catch on to this trick.
Perhaps one of the best ways to catch a fish, especially juveniles, without disturbing any decorations or stressing out the other fish is the Ciclid Trap. They are quick, easy and you probably have the materials in your house to build one right now.
Take a plastic 2 litre pop bottle, clean it out and cut off the label. Cut off the spout so that there is a hole big enough for the fish to comfortably fit through. Cut the top of the bottle off about 1/2" below where the top of the label was.
You now have a plastic cylinder with a bottom and a funnel shaped piece. Insert the funnel piece inverted into the cylinder so that it's
snug.
You should have something that looks like this:
Place some sinking pellets or crumble in the
bottom and gently place it on its side at the bottom of the tank.
The way this works is that the fish can easily swim in because
their is no impeding protrusions through the funnel into the bottle.
In other words, the funnel "guides" them into the bottle. Once
they're in there and they are content eating the food, reach in
and take out the bottle covering the top with your hand. When
they try to swim out they can't decipher the opening clearly and
panic. They're trapped and swim furiously trying to get out.
Here's some photos to better illustrate: