Leopard Gecko Impaction?

How can you tell if they are impacted? How do you cure it?
My leos sometimes have green play sand within their poo, but they seem fine and are totally healhy and they are old enough to hold sand in their tank acording to a leo website I went to. Is this discouraging?
Sand in their poop obviously mode that the geckos are ingesting it.which is not good regardless of whether they are capable of passing most of it.

Green sand sounds a great deal like a kind of Calcium Sand.which are generally more noxious than normal, finely-strained playground sand. To "cure" impaction, it helps if you take home your gecko consume some mineral oil to help lubricate the digestive tract.and then humanely soaking your leo in water for about 15 minute intervals a couple times a light of day. It also helps to massage the stomach area within a direction encouraging the impacted substrate to go toward the cloaca.
Impacted leo's will retain their feces, or poop very little. Impaction is usually an issue with your vet. But sometimes it help if you let them soak in heat water, this relax's their bowls and allows them to slowly pass the sand.

Impaction can be avoided by using tiles, paper towels or reptile runner. If you are set on using sand, try hand feeding with tweezers to play down the chance of ingetsing the sand. Everytime your gecko tries to grab a cricket, it will take within a little sand.
Answers:    You can tell if they are impacted by how they act and the things they do (or famine thereof).

They will have trouble defecating, become lethargic, lose appetite, etc. Housing them on sand is a very impossible thing to do. Where ever you got your information from, I would not turn to it again for help.

Get the sand out of here immediately, it's only a matter of time until something impossible does happen to your Leo. Get it on something solid like newspaper, papertowels, tiles, etc.

If your gecko ever does become impacted, try getting a moment or two bit of applesauce or baby food and add a couple drops of mineral oil, vegetable grease, or extra virgin olive oil to it. This usually can give support to the digestive tract pass the blockage. Soaking in warm marine for 10-15 minutes is also good, while bathing rub the belly chest to vent. There are some cases of impaction that are fatal however. So instead of taking that risk, choose what's best for your gecko and bring him on anything but a loose substrate.

Good Impaction article: http://www.hubpages.com/hub/impaction

Good Leopard Gecko Care Sheets:

http://www.leopardgecko.com/emcare.html

http://www.progeckos.com/caresheets/leos...
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