plant suggestions

its not so much the temperature but the lighting you have to consider when choosing plants. what is the wattage on your tank lights? that will help us suggest plants for you.

if you are going for a low tech/low light setup then i would suggest crypts, bacopa (frequent trimming will be needed in a 10 gallon), java moss, some of the smaller swords, stargrass (will also need frequent trimming).
 
why would your temp fluctuate so much ? The lighting, and the specs of the tank would help to pick you out some nice plants, also do you have any fish ?
 
low light, Don't have a heater so temperate water, invertabrate tank with snails and dwarf crays, max size 1/2 inch, will look into plants already mentioned. thanks.
 
Get a heater first.
 
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