Aeration For Marine Aquariums

Re: Sargassum trigger fish in trouble 7/5/05 Unfortunately, we lost all of our fish.<Sorry to hear that.> Good news is we think we know what went wrong. Looks like Oxygen levels became a problem which cause the stress that allowed secondary problems to emerge. A very harsh lesson to learn, especially as it cost the life of these beautiful animals. <Yes indeed> We are allowing the tank to stay empty for at least 30 days just in case. We do have some snails and hermit crabs that are doing well. <Good> We have a 46gal tank with a Penguin 350 bio filter, and 1 aqua clear powerhead rated for a 70 gal. tank. My question is how can we better oxygenate the water here in the mile high city of Denver? What can we do or change?  I've heard switching to a sump filter (Is that the same as a wet/dry filter?) or adding a protein skimmer. <I'd start with making sure you have at least 460 gallons per hour of circulation.  A wet/dry would be the best way of improving your oxygen levels.  The bio balls in the sump breaks the water down that allows for near 100% oxygen saturation.  If you have an air pump you could drill a hole the size of the airline tubing and put the line in the bio ball chamber.> By the way I was looking at the articles on the website and the one on aeration is blank. Just thought you should know. <I'll pass this on to Mr. Fenner.> <<Is yet another, as yet unwritten article/place holder for a FAQs file. RMF>> Thanks for your help. <You're welcome, James (Salty Dog)> Jeri