QUOTE
Ich is only vulnerable during certain periods of its life cycle, so increasing temperature is important because it speeds up ich’s life cycle and reduces the amount of time it takes to medicate the fish.
That's exactly right.

Without heat, ich can take weeks to cure but with heat it only takes a few days. Plus, warmer water also boosts the fish's immune system, helping it fight off the disease.
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I heard I could treat Ich with salt. I have a 25 gallon tank, how much do I use?!
The instructions Koko pasted are perfect, but just to additionally help you out, you need to add
25 levelled teaspoons of salt every 12 hours for a total of three treatments, except for the last addition when you shuld only make it 20 tsps (your tank won't hold exactly 25 gallons - it will be slightly less than this). Dissolve the salt completely first in some old tank water before pouring it in, well away from the fish and filter. Use only non-iodized salt which contains NO anti-caking agents. Remember you need to keep up the salt level during water chnages, so if you remove say 10 gallons of water you'll need to add 30 teaspoons of salt (although I'd play safe and add only 26-27) to the water going back in.
Keep the salt level up for
at least 5 days after the last sign of ich has disappeared from the fish; ich can lurk in the gravel for a long time and easily come back if you stop medicating too soon.
Hope this helps.