New coffe table large fresh tank

Question
QUESTION: Ok,  I have just purchased a new tank that is quite large and when it was delivered it was stocked with fish immediatly.  I know know this is not the way it is supposed to be done, but I live in Thailand and they dont do things here exactly by the book.  The measurements of the tank are 130cmlong by 90wide cm by 50cm high.  So its a nice size, it has 2 halogen lights and a inbord filter in one of the corners.  They put in many schooling fish simiar to the ones they had on the display in the mall... Now they did not have a cleaner fish so I added one that same day, with some butterfly fish, 3.  Now I also added the stress coat to the tank and the watter was looking great and at first 3 or 4 fish died wich I thought would be normal for a new tank and thought nothing of it.  So now the water was doing well and looking nice the fish were eating and all was good untill I left the house for one day to go out of town.  Come home and about 14 fish were dead and the watter was cloudy and smelly.  I think they either died from the no light for 24 hours or lack of oxygen.  In the tank there is no bubbler which I think I may need but am not sure. I have taken the glass off the top of the table and cleaned all the fish out that were dead and put more stress coat in and will wait a week to put new fish in again.  But can you maybe help me with some starter advice to my problems and see where I can trun these Thai peoples wrongs into rights so my tank can be awsome.  Also my water temp gets pretty high like high 80s is that ok for SE Asia.  It seems normal to everyone around town.  But not sure about that.  Please help sad new tank and fish owner.

ANSWER: This sounds like a saltwater tank! If there is butterfly fish in it, its saltwater. If so, I cannot help you and you need to ask a saltwater experts. Also, chances are the reason the fish are dying is because it is not being treated as saltwater. I would definately suggest finding out what type of tank it is, fresh or salt, and contacting the appropriate experts to help you. I only help with freshwater as I do not know enough about the saltwater to assist you. Sorry!

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QUESTION: one more thing, on the top of the table there are cut outs to open for feeding and such, and these have started to grow mold, like florecent in color, like a pink flourecent color. I have put them outside in the sun to dry out and will seal them with a clear coat to protect them.

Answer
Hmmm...that sounds crazy! Get me those specs and fish names and/or pics. I need exacts. Also, keep in mind that because the tank was throw together, chances are not many of the inhabitants will make it, but they may. Just a sticky situation. Let me know the specs listed in my other response.