[Fish Em]

My tank is way overstocked with mollies, has 3 cories, and 2 growing clown loaches. I had all these fish for 1 year and no problems. We did move about a month ago and clown loaches started hiding all the time for some reason.

Today I turned the tank light on and my oldest balloon molly had 1 eye missing. I immediately thought of the loaches for some reason because the water is very clean and her eyes were perfect and all other fish are very small. (Yes, I did make a mistake of getting them in my 20 gallon. They are being rehomed as soon as someone can get them.)

Later in the day, I saw another balloon molly with 1 eye missing but dead. She was in good health, but very slow. The oldest one was pretty slow as well.

I did read online and read of mass eye ball picking done by loaches. So, I wonder if this is safe to assume that is who did it?
Obviously I can't know for sure. Is there anything else that could be a reason??

 

[WaterLife]

Loaches are one of my favorite type of fish. I have tons of genus/species of loaches in the same tank with tons of other community fish, and never have I had any single fish lose an eyeball or had any fish attempt to bite a fish's eyeball. I do have clown loaches (group of 10, with the largest being 6 inches right now), with tons of different Corydoras, including tiny 1/2" juvi corys, and dwarf corydoras, and with guppies and various other fish similar in size to mollies.

Just saying that it should never happen if they are kept in suitable set ups (my tanks are overstocked heavily, but the fish are kept in proper sized groups and well fed). It's possible that the small tank size, being in a undersized group (only 2 clowns), that the clowns (and other fish) can become abnormally aggressive from the frustrations of being kept improperly. So there is a chance they may have done it. Not bashing, just explaining a possibility. I am glad you have done research and are going to do what's right for the clown loaches.

Just to question though, do you know all your water parameters? (ammonia, nitrite, etc) Since eye infections can happen due to "Un-see-able" water quality (not clarity) issues.

Still even in quarantine of new fish additions, I have not seen clown loaches become aggressive toward other tank mates. Some loaches do like to have their own caves, but territorial behavior is usually just toward similar looking loach body fish (still clowns are really peaceful for loaches).

 

[mistergreen]

nope, no other reasons.

 

[Fish Em]

Loaches are one of my favorite type of fish. I have tons of genus/species of loaches in the same tank with tons of other community fish, and never have I had any single fish lose an eyeball or had any fish attempt to bite a fish's eyeball. I do have clown loaches (group of 10, with the largest being 6 inches right now), with tons of different Corydoras, including tiny 1/2" juvi corys, and dwarf corydoras, and with guppies and various other fish similar in size to mollies.

Just saying that it should never happen if they are kept in suitable set ups (my tanks are overstocked heavily, but the fish are kept in proper sized groups and well fed). It's possible that the small tank size, being in a undersized group (only 2 clowns), that the clowns (and other fish) can become abnormally aggressive from the frustrations of being kept improperly. So there is a chance they may have done it. Not bashing, just explaining a possibility. I am glad you have done research and are going to do what's right for the clown loaches.

Just to question though, do you know all your water parameters? (ammonia, nitrite, etc) Since eye infections can happen due to "Un-see-able" water quality (not clarity) issues.

Still even in quarantine of new fish additions, I have not seen clown loaches become aggressive toward other tank mates. Some loaches do like to have their own caves, but territorial behavior is usually just toward similar looking loach body fish (still clowns are really peaceful for loaches).

I love loaches, too. We kept saying for months that we would upgrade their tank and never happened. I know they are normally peaceful. Mine used to sleep by my other fish. I think the new rescape stressed them out, or something else. The water is changed very frequently, so I wouldn't think it is that. Usually 2x week 40-50%. Sometimes more.

Bump:

nope, no other reasons.

Can you please elaborate?

So I am thinking if the 2 mollies had one of their eyes picked out, that probably would mean they are both actually not in good health. I do remember that fish often peck at sick fish that are on their last leg. Maybe I have just been ignoring that both of them are much slower than the other mollies and their health was in rapid decline. And the fact that one died. I suppose that is obvious, but never actually heard of a fish eye getting picked out often enough to take all things into consideration- like other reasons why a fish might pick out eyes. Also, I do realize it is the weekened and that I was going to get some backlash for my bogus scenario.

I just mostly came here to say many people wanted to take the loaches and so they are both gone now to a much larger tank. (About time!)

I think the issue is resolved.

 

[AWolf]

Is it impossible for a Molly to have a go at the ocular opportunity? You may have a serial eye sucker on your hands.

 

[Fish Em]

Is it impossible for a Molly to have a go at the ocular opportunity? You may have a serial eye sucker on your hands.

Could be? I guess I will have to wait and see if anymore eyes get plucked out.

 

[Diana]

Mollies are fish that need hard, alkaline water, salt is optional. The lethargy and death may have been at least partially because of the wrong water chemistry.
Clown Loaches are fish that prefer soft, somewhat acidic water.

Not compatible in the same tank. I would seriously re-do your set up(s) so the fish are in the right size tanks, with the correct water parameters.

 

[Fish Em]

Mollies are fish that need hard, alkaline water, salt is optional. The lethargy and death may have been at least partially because of the wrong water chemistry.
Clown Loaches are fish that prefer soft, somewhat acidic water.

Not compatible in the same tank. I would seriously re-do your set up(s) so the fish are in the right size tanks, with the correct water parameters.

Good point! My water is already hard, but why not experiment with brackish water since my 20 is already overrun with mollies? I will move the cories. Will my vallis be growing well in slight brackish water? I am assuming my pennywort won't, but what about my duckweed? It feels good to finally get something changed after newbie mistakes.