I bought a hood/florescent light from wal mart last week for my 10 gallon. A couple of days ago my light wouldn't turn on. Then it came on after about 15 min. It happened again yesterday. When i went to rearrange something in the tank when i touched the water it shocked me, like a really strong static shock. Problem is i threw away the box the hood came in and I lost the receipt. Do you think walmart will take this back? What should I do?