Sick Tropical Fish? Help Please!?

[James Fishman]

Hi everyone. I have a 150L (40G) tropical fish tank including.
4 clown loaches
7 rummy nose tetras
4 neon tetras
1 Silver shark
6 tiger barbs
1 bolivian butterfly ram cichlid
1 german blue ram cichlid.
Okay so for the past three days I have noticed that my clown loaches, tiger barbs and my bolivian ram are flicking or flashing, they go to the bottom of the tank go on to my driftwood and then flick rubbing their side on the driftwood/gravel. I have not noticed any white spots or anything different only that they flicker they seem fine other than that and all the other fish seem normal. Someone please help my LFS told me I have gill flukes but im not sure. Please tell me what this is and tell me what to do. I live in Australia so if wanting to tell me good products. Thankyou in advanced!

 

[DrRob]

List of questions for you.

How big are the fish (clown loaches can get to about a foot in length)?

Have you tested your water for ammonia, nitrite, nitrate, pH, or anything else? If not do so, at least for the first 4.

How long has the tank been set up for?

When did you last change anything/add any fish?

What's your routine maintenance regieme?

Anything else you can think of.

Sorry for the questions, but looking at your stock list, the first thing that springs to mind is that your bioload is pretty high and possibly more than the tank/filter can handle. Ammonia/nitrite poisoning can look like this. Ultimately you need to look at your stocking because of the loaches.

edit: sorry, forgot to mention, doesn't really sound like gill flukes to me, which in one way is good, as they're a real pain to treat.