how do snails benefit your tank? i know they eat dead plant and organic matter. but what else? ive got about a dozen small snails, about the size of the ehad of a pen and half a dozen white mystery snails about the size of a nickel. and how can snails hurt ur tank? i heard somewhere they put off alot of nitrates. Ive got them in a 125 with some plants and a single RTC... dont worry im ready to upgrade when it becomes necessary. any advice on the snails would be great and id love to see some pictures of ur snails.