help please re clown fish looking sad

[emjay]

Hiya, I am very new to all this, please be gentle
I have one clown loach, I know they don't particularly like being alone but he was this way when I got him anyway and I wanted to rescue him. The trouble is I'm not sure if he's ill or just still shell shocked from the move, day before yesterday. He harldy moves at all even when other fish are bumping into him he just sits there. We also have 3 zebra loach and these are so much more active, they still hide a lot but do swim and interact whereas my clown loach is like a complete recluse. I am hoping that a couple more clown loach mates will be what he needs, some others to school with but I don't want to upset him anymore than he is, what would you suggest? Hust for info fish are guppys tetras and 3 zebra loach and 1 clown loach thanks in advance

[Diana]

Moving can make the fish behave different for more than just a few days, so maybe that is it.
The other possibility is that there really is a problem.

When a fish moves to a new tank you need to make sure the mineral levels are the same as the tank he came out of.
The best tests for this are GH, KH and TDS. If all you have is a pH test this is better than nothing, but really does not answer the questions properly, to know that the mineral levels are the same. If this sort of thing is going to be a problem, though, it usually shows up in the first few minutes, less than an hour.