if you are sure that no copper has been added to your tank another option would be to use it as your sump and buy a larger tank that you could use as your display tank....you will want a larger tank about 5 seconds after you are happy with you salt water tank anyhow 
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Biocube 29 est 05/05/08, Koralia 1, 30lbs live rock, ,yellow tail blue damsel, pair cinnamon clowns, baby snowflake eel,Toadstool , metallic green mushroom, assorted zoos , kenya treen
180gall display, 190 pds live rock, virgate rabbitfish,bluejaw trigger, bubblletip anemone,yellow tang, sailfin tang,melanarus wrasse, cloud wrasse,
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