The tank is awfully small at 50 litres - ours is 108 with no sump and I think stability wise it is a nightmare, if it were not in our basement temperatures would be a problem and it would require a chiller.
The tank is too small for the Blue Tang - they grow to 300mm
They give no brand names for the equipment, I would not stray from Deltec and Tunze as far as skimmers and streams go, but that is my biased opinion