I always boil driftwood in a big pot before placing in tank. When the water turns brown, I drain it and boil again, three or four times until water comes out light tan. As weedkiller said, carbon in the filter will clear your water, but boiling the wood will prevent it from happening again.
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20 gal; well planted
2 angelfish
4 cherrybarbs
5 cardinal tetras
1 dwarf gourami
3 oto catfish
1 bristlenose pleco
1 crown tail betta
2 rasboras
1 cory cat
a few shrimp
If it is in fact the driftwood making the tank "fog" in a tea color, then boil it. I boil mine about three times, and then let it dry in the sun for about a week to get all the tannins out. However it really depends on the size of the driftwood.
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Obsessed with turtles, plecos, and corys for life
Driftwood can give a yellowish hue to the water if not boiled a couple times before placing in the tank. Boil it and then let it sit in a 5 gallon bucket for a few days in water. Then to get your tank water back to normal you just need to do periodic water changes.