3ft tank, got for at least 8mm.
Normal wrought iron stands are ok but you have to take into consideration that they will definately rust so it's better to get stainless steel stands instead if you have the budget.
For a sumpless setup, you will definately need a powerful HOB skimmer. The Deltec MCE600 would be sufficient for your use. Also, you will need to get a good cannister filter with a high flow rate and a chiller at the very minimum.