HOB fuge

Ok.... here's the deal. I got a HOB fuge for really cheap. Its 3.7 gallons, 18in x 4 in x 12 in.
(I was told it was WAY to big for my tank, I'm guessing they havent been to 3reef and seen some of these posts)
Is it best to put in more than one kind of algea?
I know that Caulerpa is almost imposible to find in CA, mainly because they put a ban on it (why its illegal I'm not sure)
I was going to put in some Mud & sand across the bottom. Yes I have heard mud is a waste of money, but I dont own a cat. layered on top of that some rock rubble and some algea possibly Cheato.

Would it be better if I put in two kinds of algea? or would the one be enough?
How thick should the substrate level be for a smallish fuge? 2 inches?
and did I seriously screw up and buy a HOB fuge thats too large (or small) for my tank?

 

Ur refugium is definitely not too large or too small. If i was you i would make the sandbed about 4 to 6 inches and throw some chaetomorpha and LR and proper lighting pc or halide or grow lights and it should be fine. About ur question on the ban of caulerpa it can mess up plumbing in pipes from people flushing it and its rapid growth rate.