Looks bigger than a 38 in pictures, i'm still not totally sold; with that said....
INNEED, you need to give all live stock back to the store that sold it to you, and have them hold all of it, free of charge! They should do that, as everything in your tank is going to die.
-Your tank is on a table that is not big enough for it, the tank could break. -You need a "real" stand.
-Your filtration is a joke, I'm sorry to tell you this, but you have virtually no chance with the filtration system you have on there.
-You have fish/eel that will out grow your tank.
-Your eel will eat the fish in the tank---however, it is really cool, but not the point
-eels will "climb" out of a tank if the tank is not properly covered
--Triggers(not sure about yours, looks like a niger Trigger) like to bite wires in the tank, you have many that could easily send electric current through entire tank and shock you or livestock, or god forbid a major electric issue.
You have a glass heater in the main display...that is a no no b/c if it breaks you have a major issue with glass/"lectricity"
and this is only what I can see from the 2 pictures.
Please take my advice and save your money(spent on Livestock) and the lives of the poor animals, and return them to the store to "just hold" while you learn what it takes and have a proper setup.
The store should be willing to do this b/c you were totally taken advantage of, and sold stuff you could not take care of at that time.
Please take my advice
. first thing you need is to read ! every where train job if you can lol at home read this forum "noob section" i still read it. like you said there is no stupid question... but you also need to do some reading. if a sting ray is what you strive for ...and you are serious about it i believe you can do it ....but in this hobby nothing good happens fast nothing! point blank. that being said ..do some reading if you need me to point you out a couple of articles just pm me. 
