I found this article very useful for understanding ich
http://www.peteducation.com/article....articleid=2421
And this one about treating ich on loaches
http://www.wheelpost.com/Ichfish.html
We had a similar problem a while back. After 5 days of using Maricide (basically the same thing as Aquarisol) we saw more spots and more fish with ich.
We cleared out the meds (water change and carbon filter) and switched to CopperSafe. Having read about some people's experiences online (especially at
www.loaches.com), we added 1/4 dose every 3 hours until we got to full dose, just to make sure the meds weren't harming the loaches. We also made sure to take off the volume of gravel/plants/decorations from the total volume of the tank when calculating the dose of meds.
The ich began clearing within 2 days, although took a while to finally leave. The parasites can apparently stay dormant on a fish for a few weeks. Strangely enough, although our tank was at a fairly high temp, the ich didn't seem to go through its cycle any faster.
We are still trying to work out what stressed the fish into getting ich, although it's kind of hard to pin down. I know it certainly stressed us out having fish with ich.
This is just what we did. Some people say to use the salt/heat method, and it has worked for them. Our loaches certainly had it worse than other fish in the tank, and that worried us hugely.
Good luck in getting them back to full health.
