PLEASE HELP MY SICK LOACHES

[Mrs.Muk]

I have searched forums for two days now and cannot find anything to match what's happening. I have two nine-year old loaches in a well-established 75-gallon tank. I have since learned I am supposed to have no less than four, but I have had these two since they were little. They always kept to themselves, each inhabiting its own log or other hiding place. Just two days ago, they started acting strange, squeezing into one log together, and rubbing/pushing on each other. Oftentimes one will be upside down. I have noticed no red streaks, spots, bulging eyes. However, I do believe my tank has been compromised because I have had several dead fish. My fish store guy told me it was probably bacterial and to give them several doses of Furan-2. Has anyone heard of this behavior and are they going to be okay?? I am so attached to them and it's so hard to watch what seems to be them suffering.

[Diana]

Loaches can behave in ways that other fish do not, and it is just fine. I can suggest a few things.
1) each living in their own favorite place is very common. Even when you have more than 2 there will be different places for some individuals, and others will group together.
2) Change of habit, now they want to live in the same area, but are not fighting about it. This is OK, Loaches are social, and even Loaches that prefer to be alone, or sleep separately may change their mind. However, you might do some extra cleaning in both the homes, but especially the area that is no longer being used. It might be that the water does not move so well there and something has accumulated that the Loach does not like.
3) Interacting more, but not fighting, is good. One possible reason is that they are maturing, and you have a male and female.
4) Upside down is not a problem at all. Some loaches do this a lot, others (even the same species) seem never to do it. Have a look at some of the pictures here of Loaches doing odd things. Sleeping on their sides or back is common.

5) Recent deaths in the tank...

I would do a few extra water changes that emphasize cleaning the floor of the tank. A lot of disease organisms and parasites can build up when there are dead spots in the water flow, or stagnant areas such as under the substrate. By doing a few more thorough vacuums in these areas you will be reducing the level of decomposing organic matter in the tank. If it turns out you do need to medicate for anything this will also help the medication act against the disease organisms, because there are fewer other things living in the tank. Lift up all the rocks and logs, move the plants enough that you can get the vacuum around the base of the plants (a smaller vacuum or a piece of tubing is better to get close in to clean around plants).
You do not have to do this all at one time. Lets say you did a 25% water change, and cleaned 1/3 of the tank today. Then in a couple of days you did another 25% and cleaned another 1/3 of the tank... and so on. It would take about a week, and perhaps 3-4 sessions, but all the tank would get cleaned this way with less disturbance to the fish. Clean the filter, too, of course.

[starsplitter7]

I agree with Diana. DO lots of water changes, and make sure the water is healthy.

Loaches hanging out can be a sign of growing friendship. SLeeping on back and sign with no sign of illness is perfect. I have seen mine even nose down, on their backs, . . .

What kind of loaches do you have?

[redshark1]

Good luck helping your loaches.

If there is a dead fish in the other log this would explain the behaviour as one loach would have to find another home.

Hopefully not but it has happened to me in the past.

It would seem to me to be a good idea to do everything possible to improve the water quality. This includes improving biological filtration. It may be helpful to do some reading on the subject so you can get your tank conditions as good as possible. Then hopefully your lovely loaches will live another 9 years (or even more!).