Doggy Solutions™ has made the following observations when comparing the use of gravel and synthetic K9Grass:

• When gravel is used, most of the urine drains through to the litter layer below which is ideal. The litter absorbs both the liquid and the odor from the urine. The synthetic grass that Doggy Solutions™ offers (K9Grass) has a knitted mesh backing to enhance drainage. This K9Grass is far superior to other synthetic grass products on the market that have a perforated plastic backing. These products tend to hold more urine and develop odor quickly. There is also an anti-microbial agent incorporated into the K9Grass blades. This antimicrobial deters the growth of microorganisms and the associated odor. Since the synthetic K9Grass has significant surface area, some urine may dry on the grass blades. Particularly when the potty is set-up indoors, more frequent cleaning of the synthetic grass pieces may be necessary. Fortunately, this material can be easily cleaned and disinfected by soaking it in a tub of dilute sanitizing or bleach solution. The gravel also needs to be rinsed with a dilute sanitizing or bleach solution periodically.
• We have found that it may be somewhat easier to remove solid waste from the gravel. If necessary, a disinfectant wipe can be used to wipe the synthetic K9Grass clean.
• Because the K9Grass is more similar to real grass, it may be easier to train some adult dogs to use the potty when the K9Grass is used as the substrate. The training process for adult dogs varies widely from dog to dog and some dogs accustomed to grass are easily trained to use the potty containing gravel.
• Some dog and puppy owners prefer the look of the synthetic K9Grass.
• The trays containing the synthetic K9Grass pieces are lighter in weight than those filled with gravel and may, therefore, be easier to handle. Our potty systems are now made with "double-sized" trays when the K9Grass is used as the substrate which provides a more continuous surface for your dog or puppy.
• The initial expense associated with the pebbles is less than the K9Grass.
• Finally, some dogs, particularly males, like to scratch or dig after they eliminate. If this is the case, then the K9Grass is more desirable, since the pebbles can get kicked out of the potty. Also, some puppies like to play with the pebbles.