5 Techniques for Catching Fish in a Marine Aquarium

At one point or another, every marine aquarium hobbyist is faced with the necessity of capturing and removing a fish from a fully operational system—perhaps because the specimen is bullying tankmates, the victim of another specimen’s bullying, sick or injured, etc. Whatever the reason, the prospect of catching a fish that has “home field advantage” in a functioning, aquascaped aquarium can seem daunting—sort of like capturing a chipmunk in a woodpile.

Chasing the fish all over the tank with a net will only stress the specimen and put it at risk of injury as it dashes around frantically, attempting to evade capture. Removing all thelive rockand otheraquascapingisn’t necessarily a practical solution either, especially if you have a reef system full of corals.

好消息是，您可以使用许多不同的技术来捕获鱼，而无需颠倒整个水生世界。这里有五个示例：

＃1：两个net击倒

If you have sufficient room to maneuver in the tank and the fish hasn’t already “gone to ground” in the rockwork, you can try the Two-Net Takedown. This technique, as the (completely fabricated) name implies, involves the use of two fish nets. The first is utilized not to chase down and nab the specimen, but to encourage it to swim away in the opposite direction—and hopefully right into the second net that you’ve strategically positioned in its line of escape.

You’ll probably get only one shot at the Two-Net Takedown because the fish will very quickly get wise to your intentions and will hide in the rocks as soon as a net comes into view.

#2: The Nocturnal Nab

天黑后的几个小时，当受欢迎的标本休息和迟钝的时候，可以是带网的好时机，但前提是只有当它的睡眠区相对易于进入时。例如，我的125加仑水箱中的番茄小丑鱼总是位于溢流室旁边的水箱的一个特定顶角。如果我需要捕获它，我可以在天黑后几秒钟内将其净化。但是，如果标本睡在直播中，这种方法将无法正常工作。

Patience is key with the Nocturnal Nab because you don’t want to attempt it immediately after lights out. You want to wait until the specimen is good and relaxed and dreaming its little fishy dreams before making your move. Also, “spotlighting” the specimen with a flashlight beam just before deploying the net will disorient it further and facilitate easier capture.

#3: The Baited Trap

If netting isn’t practical or successful, you may want to try setting a baited trap for the fish. There are commercially manufactured traps of various designs on the market that you can buy, or you can construct a simple, inexpensive DIY trap out of a common plastic soda bottle. Here’s how:

Using a sharp utility knife or razor blade, carefully cut off the top (approximately) one-third of a thoroughly rinsed two-liter soda bottle. Then, invert the top portion of the bottle into the bottom part so the threaded opening is facing downward. To secure the pieces together and prevent the top part from falling inside the bottom part, apply a few small dabs of aquarium-safe-silicone or super glue gel where the two sections meet. After the adhesive has dried, bait the trap with a sinking food that you know the fish will eat and place the trap on its side at the bottom of the tank.

Note: Depending on the size of the fish you need to capture, you may need to widen the opening of your DIY trap.

Again, patience is a must when using the baited-trap method because it may take several days for the specimen to get accustomed to the trap being there and to feel confident enough to venture inside. Then again, some fish are just too savvy or suspicious to fall for this ruse.

＃4：“ Toto，我感觉我们已经不在堪萨斯州了”技术

Okay, that name is really a stretch, so please bear with me. Essentially, this technique involves removing the entire rock in which a specimen is known to be hiding, transferring it to a rigid container under water, and then moving the fish, rock and all, to its new home—sort of like Dorothy being swept away to the Land of Oz by the tornado (see, I told you I’d bring it back around!).

In order for this method to work, however, very specific conditions must be in place: The fish must be hiding in a cave, nook, or cranny in a single chunk of rock (for instance, I once had aflame angelfish(Centropyge loriculus) that, at any sign of danger, would tuck itself headfirst into a very narrow “pocket” on the underside of a piece of live rock), and the rock must be easily accessible without tearing apart the whole pile.

＃5：经济衰退

有时候，除了剥夺鱼至少一个优势的能力，没有什么是在多个飞机上逃脱的能力。这样，我指的是降低坦克中的水位，几乎一路一直到底部，以使成功捕获的几率对您有利。

As you might imagine, this method is not ideal for reef systems, as it would leave most or all of the corals high and dry (some species are more or less tolerant of air exposure than others). Even in fish-only orFOWLR(fish-only-with-live-rock) systems, this technique needs to be performed quickly and efficiently so the rockwork is exposed to air for only a brief period, thus ensuring that the biofilter isn’t compromised.

The best way to expedite the process is to use a hefty submersible pump and tubing to rapidly transfer water from the tank to a separate container and then back again.

What’s your secret?
If you have a technique for capturing fish that isn’t described here, we’d love to hear from you! Please share your idea with your fellow salties in the comments section below.