Hi. FISH EMERGENCY!!! PLEASE ANSWER!!
I have a 2.5 gallon tank with 2 guppies. I have had one of them for 1 month and the other for just a few days. They have been living fine together until this morning. They are lying next to each other on the bottom. I am assuming it is because they are cold? Their temperature is usually around 72-75, but it dropped to 68. I have turned the light on above the tank and I want to warm the water, but don't want to put them into shock. Also I noticed that just now that they have little white spots on them!! Any suggestions? I love these guys and do not want them to die!

Your fish would seem to have Ich - an opportunistic parasite that has probably hit because the fish are cold. Every pet store has tons of meds, but since it's Sunday night, every pet store is closed.
As a back up, home remedy, you can use non-iodized salt (sea salt, kosher salt or picking salt) at three teaspoons per gallon. Ideally, you should have a heater and raise the temperature to 85 to battle that one. Don't do anything to raise it without a heater, as up and down temps will help the parasite, not the fish.
Warmth accelerates the life cycle of the parasite, and makes it easier to kill. At 85, most forms of ich (it is many different, related species) begin to die.
Tomorrow, you can get an ich med - avoid any copper-based ones because of the salt, and aim for one of the dyes.
Take out any carbon in the filter.
Good luck.

Ich looks like the fish have been sprinkled with sand or sugar. If you can post a pic that would be more helpful.

Sounds like ich like said above, but until I see a picture I can't be too sure.

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warm the water gradually...do you have an adjustable heater in that tank?

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