Disappearing Fish

[linyo]

Hello,

I'm new to Aquarium Advice, so here's a little about me and the reason I'm writing. I'm married, have 4 kids, 2 dogs, 2 cats and a 55 gallon aquarium. I'm not looking for advice on my marriage, my kids, or the 4 furry critters that live here . . . but I sure could use some help with my aquarium!

I have a 55 gal freshwater tank that I set up 4 or 5 years ago starting with 10 or 12 mollies that multiplied into probably 50+ fish over the first couple years. Later into the first year I added 2 (yoyo) loaches, and 3 Chinese algae eaters--two of which died for unknown reasons, after which I added 6 cory cats. I had some parasite that killed a lot of my mollies and, because of the treatment advice of a local pet store, I lost my first 6 cories--which they replaced.

Now my fish are just disappearing! I live near a lake, but I'm pretty sure they aren't sneaking out at night . . .

What I have left in my tank as of this evening is 1 loach, 1 algae eater, 3 mollies and 4 cories. A week ago or so I still had all 6 cory cats, now I can only find 4. I cannot find anything at all (no bones or anything else) left of the fish that are disappearing . . . they are just gone . . . vanished . . . poof . . .

I'd accuse one of the cats, except the tank is covered and there is no where for the de-clawed cats to get access to the water.

I do suspect the algae eater, though, because he(?) seems to chase the other fish around the tank sometimes. Then again, the loach does too. And he has his little hideout in a "hollow tree", which he backs into. A year ago I found the smelly remains of the other loach inside that "tree." I haven't found any other carcuses since, but I'm wondering if the loach is dragging his tank mates in there and . . . . . . ?

I just don't know what's going on . . . can anyone give me some ideas where to look to resolve this problem? I would like to put more fish in the tank, but not if they're going to slip off into a black hole somewhere never to be seen or heard from again.

Thanks in advance.

Linda

[Purrbox]

Welcome to AA Linda!

Just to rule some things out, could you report the test results for Ammonia, Nitrite, and Nitrate?

Fish can disappear for a variety of reasons. They may die of old age and the remains cleaned up by tank mates. They may become and unwilling snack for a tank mate. They may simply be hiding. They may find a way out of the aquarium that we didn't think possible to remain unseen or carted away by a furry pet.

It would be helpful to get an exact id on both your loach and algae eater. This will tell us if you have a fish that gets agressive as it gets older and what type of diet they usually have. If you don't know for sure, then posting pictures for us to id would be beneficial.

[Alaris]

Originally Posted by linyo

Later into the first year I added 2 (yoyo) loaches, and 3 Chinese algae eaters--two of which died for unknown reasons, after which I added 6 cory cats.

She did ID her fish: yoyo loach and Chinese algae eater.

Here's something I found about CAE's: Chinese Algae Eater, Gyrinocheilus aymonieri, Also called: Siamese Algae Eater, Indian Algae Eater, Sucking Loach

It says that young CAEs are quite peaceful in a community tank, but as they get older (about 4in) they will be very aggressive. One comment even stated that if they don't have algae to eat, they'll start snacking on your other fish.

[MichaelsLilGray]

...holy crap I never knew they would go to the carnavor side. but from your story. i dont see anyother idea. What kind of Gravel/sand do you have in the tank?

[Purrbox]

Originally Posted by Alaris

She did ID her fish: yoyo loach and Chinese algae eater.

Thanks Alaris, I didn't catch that they were identified earlier in the post. I agree that the Chinese Algae Eater is the most likely suspect.

[linyo]

Wow. Thanks for the input. I have small natural gravel and natural "landscaping" objects. My CAE is over 3 inches, and I really do suspect he is a snack bandit. But I never see him actually eating any other fish.

It is possible some of the mollies jumped out of the tank near the power filter, in which case they would be under the cabinet where I wouldn't see them but my cats might.

I feed algae wafers, shrimp pellets, bloodworms and something the local pet store recommended that's just called "small pellets"--they look like little black beads.

As for the tests, I will run those later tonight and post the results. Right now I have 4 little ones to get into bed.

Thanks again for your replies.

~Linda