well, petal flower, what type of snail are you looking at? probably a 'mystery snail' right? well, usually htey are brigs, a species of snail most commonly sold in petstores.
they are not algae eaters, as is commonly believed...they must have supplemented food (tubiflex worms, algae wafers, sinking fish pellets, veggies)
calcium supplement is also good, but not 100% mandatory
PH of your water has to be pretty high for proper shell growth and snail health like, 7.8-8 ish is good
they dont need heated water, but will be more active in warmer water, although a shorter lifespan accompanies warmer water.
i think thats about it for care...oh, rule of thumb is 2 gal of water p er snail
they come inlost of pretty colors too! good luck, keep us updated!