setting up an aquarium for albino/regular irredecent sharks(Catfish)

Question
Hello thanks for your time,
I got a 40 gallon tank and aqua clear filter for 20-50 gallon tanks I don't know the exact age of the tank but it is probably at least 5 years old. I want to setup an aquarium for albino and regular irredecent sharks (catfish), a relative of mine had these when I was younger and has told me that they like sand and rocks, I was wondering if you would be able to tell me what kind of rocks(If indeed they do like rocks), background, and lighting these fish like and if possible what they eat and what tempature they enjoy.
As I said before I am looking to setup a tank so I don't have a water change schedule or any fish in this tank so I can't really answer those questions.
Thanks again for your time, it is really appreciated.  

Answer
Hello,

The expert you asked the question has taken too long to answer, So I decided I would take the question and answer it for you because I own these fish myself.

These fish light just barely lite places, generally in little caves or other places where they can hide from anything. they dont light rocks too much because they are alot softer that the other fish due to not having any scales. So they like little caves or other little holes where they can barely turn around. also they do like a few plants around because they feel like they are more hidden in them as they swim around in search of food. Lots of the catfish big and small seem to get along good, and in fact even share the same cave sometimes. They all like to eat Dried shrimp pellets, and just normal fish food. However make sure that you feed any other fish first so that the pellets make it to the bottom feeder fish. they like the temp. around 72.5 degrees F.

As far as water changes, you should change the water once a week. You should take about 25% of the water out and add new water. To insure that your fish stay safe and healthy I strongly suggest getting a box of fish salt. you should put 1/2 a tablespoon for every 2 gallons with these fish. the salt well keep their slime coat good as well as help maintain the water condition. You should use Distilled Bottled water unless you know that you have tested and have good tap water. Even though they like little light it is a good idea to get a very bright florecent light, and then just make a bunch of shaded caves. At least one per Catfish that you have.

If you have any further questions feel free to ask!

Thanks,
Exp. Michael Mulcahy