Loaches Online Forum

I am sure it has been posted a thousand tines: I have heard how susceptible clowns are to Ick. I am setting up a 90 gallon and am thinking of getting some clowns. Also, no problems with corys, other loaches, sharks etc?

All the cats and Loaches that I know of can get Ich.
The very best prevention is to get the fish from a reliable source, then quarantine the new fish.
You can run a UV sterilizer on the Q-tank from the beginning. Run it for 1 week. This would likely kill the Ich that came in with the fish from the store. Then, if you do not see any Ich, turn it off and watch. Watch for any sort of disease or parasite. Probably also a good idea to treat any bottom dwelling fish for internal parasites while they are in quarantine.
Maintain quarantine for at least 1 month PAST the date you stopped medicines and any other treatment.

Catfish (Cories, Loricariads, certain 'sharks' and many other fish): Can get Ich. Tricky to treat because they are 'scaleless', sensitive to most meds.
Loaches: Can get Ich. Tricky to treat because they are scaleless, sensitive to most meds.
'Sharks': There are many species of fish with that common name.
~ Catfish 'Sharks': See catfish
~ Bala Sharks: Can get Ich. If I remember correctly they are tricky to treat because they are fine scaled. Sensitive to most meds.
~ Epalzeorhynchus spp: Red Tailed Shark and several others: Can get Ich, not sensitive to most meds.
Tetras: Most are fine scaled, so more sensitive to meds.
Barbs: Less sensitive to meds.
Ananbantoids: Read the label. With their labyrinth organ they may be sensitive to a different range of meds than many other common fresh water fish. IME they did not get Ich as easily as some other fish. They are not immune, through.
Livebearers: Less sensitive to meds.
Cichlids: Sensitivity varies. Do more research.