Your buddy got algae from boiled sand? Then you definately don't want him helping you with your tanks

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Boiling sterilizes the sand so he had other problems.
If you have the time and space spred the sand out and a clean surface and let it dry in the sun for a week to kill off most algae and parasites.
If not...
Clean the sand first with bleach, then dish soap and finally rinsing to remove what you washed free and all the bleach/soap you added. Depending on the amount of sand your doing this will take alot of water. If you can't
taste the bleach or soap after you rinse it then rinse it once more and your done. If you haven't gotten ill after a week then it should be safe for your fish.
Black and green sand huh? Sounds like it could be worth the trouble.
Some people in the States might be willing to harm someone for substrate like that

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Let us see some pix of your process and your success.
Dr Joe
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