Real Simple. Real green. We saw this green tip in the latest issue of Real Simple magazine. Fill an empty soda bottle (or two) with water and place it in the toilet tank away from the operating mechanisms. This will reduce the amount of water it takes to refill your tank, thus saving water with every flush. (This tip is meant for older toilets, not new high-efficiency ones.) Other sources suggest putting a few inches of sand, gravel or pebbles in the cans so they sink to the bottom of the tank. Although we can't see any advantage over soda bottles, you could also purchase a Toilet Tank Bank for about $2 which accomplishes the same thing. Besides conserving water, this green idea will also conserve money on your water bill... which you could easily put towards the purchase of an even more water-saving dual-flush toilet. posted originally from: AT:Nursery We especially hope these owners give this a go. Has anyone tried this at home?