Irredecent and albano sharks

Question
Hey Karen, beginner here.  I recently got a 55gal tank and have furnished it with small gravel plenty of hiding spots like a cave and a titanic with openings as well as a variety of artificial plants.  I have a penguin 350 bio wheel filter, and before adding my fish made sure everything was clean and added the kits and let everything sit(with he filter running for a couple of weeks.  I added my beta, along with an iridescent shark, albino, two Chinese algae eaters and on small pleko.  my two questions are how exactly should i go about feeding the two sharks, i was told my tetra tropical flakes are fine by friends and the shop keeper.  However it seems like they do not touch them. I have heard certain fish like to eat in certain conditions like darkness and such.  what should i do?  Second the albino is rather shy and hides most of the time which i think is normal, but the iridescent seems to by swimming widely back and forth facing the glass.  is this a normal adjustment thing or should i be worried? please help!

Answer
Dear Brian,
Flakes are ok for your catfish. But they would probably do better with special catfish tablets and frozen and freeze dried foods of all kinds like redworms, tubifex, Brine shrimp, krill, ect...
~ Unfortunately, I am sorry to say, that Iridescent catfish are not suitable for your aquarium. If cared for well, these catfish easily reach 2 feet in length and have potentail to reach 4 feet long as well. If you would like to see Iridescent sharks as big as some can be- visit here-
"http://www.planetcatfish.com/catelog/species.php?species_id=172"

I'm sorry to tell you, as a beginner this, but your current  fish selection isn't really the best. It would have been much better to start with simple and small fish.

Iridescent sharks really need to be in a small school to feel safe. They are generally very active fish that need plenty of room in the aquarium to swim back and forth as they do. They are also greatly prone to spooking and ramming into tank decor without any self-regard...

Is the albino catfish also a Iridescent shark? If not, then it could be considered normal if he is a different species to hide for most of the day. Since most all catfish (except iridescent) tend to like to rest in hiding places during the daytime.

Please make sure your aquarium doesn't get too high in ammonia or nitrites since this is a newly setup aquarium. You can easily test for these levels with an aquarium test kit. Should these levels go above safe bounds, be sure to do an immediate 30-50% water change right away. Making sure the replacement water is equal in temperature to that of your aquarium and is dechlorinated everytime with a good water conditioner.

I really hope this helps!
Feel free to write, I am more than happy to help you with anymore questions or concerns you may have!

Best wishes,
Karen~