It has been my opinion for many years, that unless you catch it before any die, then Metro is fine to cure it.

BUT...once you loose a fish, or fish go a couple days and no eating, there is nothing that works better than CLOUT.

Use CLOUT in this method.

Start with a 50% water change. Then dose as prescribed on the bottle.
Then Second day dose as the bottle says
Third day dose as the bottle says.
4th Day, 50% water change and dose per bottle...

Always treat for 5 days if even all fish are eating.

Treat until all fish are eating, and fully recovered.

Once your treatment is complete, 50% water change and add carbon.

Only deep gravel vacuum during the first water change and the last one.

Then on your next couple water changes, do not deep gravel vacuum.

Any silver-sided fish or scaleless fish should not be treated with CLOUT.

I have used CLOUT on ectodus and not had a problem.

With the silver-sided fish, you need to dose 1/2 strength, then sometime later dose the other half.

In fact with any silver-sided fish, any med should be taken easy until you know they can handle it.

As time progressed I was able to fully dose the Ectodus, but I have read several accounts where challochromis, paracyps, and some featherfins have died while full dosing CLOUT.

You can alleviate the blue stain by having a higher pH and performing the water changes during the treatment. If needed, perform 50% every other day if silicone is your worry. The blue stain/color comes from the Malachite Green component of the medication. It's function is to kill free floating bacteria's, and external parasites.

Best of Luck!!!