If you want a severely inexpensive skimmer, you might want to do a yahoo or google search on DIY skimmers. I've heard of guys doing a skimmer for a 200 gallon for around $20. Though without experience with skimmers the smarter route would be to buy a name brand skimmer. You aren't going to find a skimmer for less than 100 bucks that can handle a 75. Are you going to have a sump or do you want to hang a skimmer on the back? If you are going to want to go with a sump you may look into the Berlin's, Red Sea's, and Sea Clone's if you want to go with the cheaper brands. Just remember that you get what you pay for.
Clint
