How to Remove Unwanted Fish from a Reef Tank

Okay let’s admit it, we all make mistakes. And sadly I must admit that I probably make more than most. As we all know there are two types of mistakes: omission where we don’t do something we should have, and commission where we actively do something that causes the problem. Adding a fish to our tanks is unique in that it can be a mistake of both types.

It may be omission, in that we did not do our homework before adding it or we didn’t realize that it grew so big or would eventually eat all of our prized corals, etc. And the mistake is always one of commission because fish do not suddenly just appear in our tanks. Regardless of which type of mistake it is, most of us at one time or another have added a fish that we regretted adding to our tanks.

It could be a cute blenny that the LFS swore would not mow down our corals, or an angel that we had for years, that suddenly went rogue and decided to eat all of our LPS or a fish that we knew was risky, but we knew that if we kept it well fed there would be no problem. The reality of this hobby is that this happens to all of us, and usually more often than we like to admit, so once we acknowledge that there is a problem, what do we do about it. For even in a small nano tank, it is darn near impossible to get out even one fish without tearing down the entire tank and for a big reef tank you may be looking at entire day if you need to tear down the tank.

由于多年来我犯了错误的鱼，我犯了无数的错误，我已经掌握了从最大的珊瑚填充坦克中去除不必要的鱼类的艺术。即使我爱咸水鱼几乎和珊瑚一样多，但我还是坚持这样的规则：如果一条鱼开始吃我的珊瑚，那就去了。通过这样做，我已经意识到，在不被抓住的情况下，鱼比我聪明得多，但它们不那么耐心。

With some ingenuity and a lot of patience I have been able to remove almost every troublemaking fish that I have added to my tanks, without having to resort to tearing down the entire tank. Doing this does require that you understand the fish’s behavior in order to figure out the best way to catch it as there is no one method that works for all of them. But it can be done.

We will start with the easiest method and the one I use most frequently:鱼陷阱. Everyone who has been in the hobby for any length of time has seen this big box with a sliding door that in the best case the fish will swim into where they will be trapped. Oh if it were only that easy. Sure some fish are not that bright, but are curious, so they will swim in right away to be trapped, but many will not.I could not figure out why and realized that if you look at it a fish trap looks like a big open mouth. And like I said fish have proven smarter than me, so they do not swim into a big open mouth. So to try and remedy this problem I do several things.

首先，我可以得到最大的陷阱，可以适合我的水箱，而不会击倒所有珊瑚。然后，我在开口周围粘合了珊瑚，岩石和砾石，所以它看起来不像嘴巴，第三我计划至少花几天时间上班。在第一天，它只是休息或悬挂在水箱中，以使鱼适应它。在第二天，所有放入水箱中的食物都放在盒子里。为此，使用了喂食烟囱或贝斯特，以便食物在陷阱的后部。

On the third day the door is placed on the trap and adjusted so that lowering it can be accomplished quickly. Also during this time you need to get the fish accustomed to your being near the tank and near the trap so stay near the trap as you feed and keep your hands near the door, otherwise the fish will bolt if they are not used to your presence.

Once the fish are accustomed to all of this food is introduced on a regular basis and in the best case the fish I want to trap will go in to eat and be trapped and removed. Sadly this is the exception rather than the rule with using this type of trap, because for some reason fish just inherently know that this is a trap. That may sound funny, but I have no other explanation for why this doesn’t work more often.

因此，由于这种情况并没有像我想要的那样频繁，所以我开发了一种称为篮子的陷阱的变体。对于这种方法，网状篮子，就像可以在大盒子硬件商店中捡起的池塘一样，请参见图片，放置在水箱中。使用了两种磁铁，一个在篮子内，另一座玻璃将篮子固定在适当的位置。篮子放在水面以下约一英尺左右，与陷阱一样，所有水箱的所有食物都放在篮子里。

随着鱼类习惯从篮子里喂食，我的存在篮子逐渐向上移动到储罐中的越来越高，因此最终仅在地面以下仅4-6英寸。同样，并非所有的鱼都会进入其中，但是如果我想卸下的鱼，那么所需的一切就是要使篮子一旦所需的鱼就会迅速将其抬起到表面。我应该指出的是，就像陷阱一样，您通常只有一枪就知道这是一个陷阱，他们不会第二次进入它。因此，这就是为什么耐心在这里关键的原因，因为鱼在这些陷阱中不舒服的情况下会更快地飞出。
与上述方法不同，这些方法仅依靠诱饵和陷阱，这些方法需要更多的精力。首先是我开发的一种用于纳米坦克的技术，当时我知道wherea small fish, like a coral eating goby or a pugnaciouspseudochromis, sleeps or likes to hide. For this method a long piece of 1” diameter flexible tubing is needed as well as a red LED flashlight.

The first step in this process is to see where these small fish sleep or where they like to hide. To determine this, I visit the tank after all the lights are out and use the red flashlight to see where the fish are without their being able to see me. Generally these small fish are very territorial so I check out the tank for a couple of nights at least to make sure that they are in the same spot each night.

Once I have determined their favorite spot, I get the hose ready by starting a siphon in it and either having it flow into the sump or into a large bucket. Due to its large diameter the hose will siphon water from the tank very quickly so make sure to use a bucket of adequate size. Once the siphon is started I stand on the hose and again locate the fish with the red flashlight. The hose is then directed to where the fish is resting, my foot is lifted from the hose and if all goes well the fish is quickly siphoned from its lair.

有几个钥匙可以很好地进行。首先，确保鱼处于良好的位置，可以沿着长轴绘制，而不是将其侧向拉入软管，在那里它会受伤或杀死。第二次尝试在您移动软管时，即使是轻微的振动也会导致鱼移出位置时，请不要撞到任何东西。在鱼被困并将其放入合适的容器中时，第三秒停止了软管，因为如果您让它流入污水池中，您会回到试图捕捉到比捕获捕获更熟练的鱼类。
I also use another technique for when larger fish sleep above or in front of the rocks and corals in my tank. Again the first step is to assess where the fish sleeps and to make sure you have clean access to it. Once this is ascertained, again using the red LED flashlight, get a net ready just slightly larger than the fish and get it as close to the fish as you can.

Once it is close switch on the brightest white light that the flashlight provides. This bright white light will temporarily blind the fish and kind of stun it like a deer in the headlights so it won’t move. This will provide enough time to net the fish quickly and remove it from the tank. I have used this technique to remove aiptasia eating filefish as well as some aggressive wrasses and tangs.
If the above listed techniques don’t work I then resort to more “nuclear” options. While not as nuclear as tearing down the tank they are a bit more traumatic to the tank and the fish. In the first method clear plastic is fastened to the first piece of pvc pipe that is at least as tall as the tank. The clear plastic is about two-thirds as long as the tank and is fastened to a second piece of pvc. I use gel super glue to fasten the plastic while everything is dry.

放置了两根管子，以使一块牢固地靠在油箱的远侧墙壁上，第二块被放置在前玻璃和坦克其余部分之间的分区，开口就像一个大的V.我通常会发现这最有效，如果储罐内的流量减少或关闭，则在完成此操作时。

为了防止鱼通过底部的塑料逃脱，将小块的活岩或珊瑚沿着塑料逸出，以防止其向上移动。与其他类型的捕获一样，所有喂食都是在塑料前进行的，因此鱼必须在该隔板区域内才能进食。一旦所需的鱼游到该区域，可移动的管道被拉到前玻璃，远离逃生，可以将鱼固定在塑料中的玻璃上，或者可以从分区区域中净化。

Like I said this is a more traumatic means for catching an undesired fish. Sometimes even this does not work as advertised so a bit of ingenuity may come into play. For instance, one angel that I tried everything to catch simply would not be fooled with any of these methods. I was removing him because he suddenly developed an appetite for large fleshy lps. So since I had run out of ideas I tried placing a couple of open brain corals in the front in front of the plastic. Amazingly within 10 minutes he got over all of his shyness and swam into this partition trap so I could finally remove him.

So if all of this fails and you still do not want to tear down the tank there is one last option that I have only used once, but have heard of its use many times. The old bait on a hook method. In order to do this you need to get the smallest hook you can find. Remove the barb from the hook, as you don’t want the hook to set and damage the fish’s mouth and then find bait that the fish finds appealing.

In this instance you then need to attach the hook to monofilament line and then get the hook to be near your intended target. However, unlike normal fishing this is kind of the opposite. Since most of the fish in your tank are not scared of hooks and are always hungry they will attack the hook if you aren’t careful. So in this form of “fishing” you actually have to try and keep the hook away from the other fish and get it near you target. Needless to say this requires a lot of focus and patience and it can be quite tiring. As I said I only used it once to remove some incredibly aggressive and smart damselfish and it took almost half a day to do so.
Hopefully none of you will make the same or at least not as many mistakes as I have made. However if you do by adding the wrong fish to your tank at least you now know that there are ways to remove them without tearing down the entire tank.