That price is very appealing! And since it works with the Apex, thats nice also.WP-10
http://www.fish-street.com/jebao_wp-10_4000l_wave_maker?category_id=35
WP-25
http://www.fish-street.com/jebao_wp-25_8000l_wave_maker?category_id=35
Jebao (chinese brand) is the maker, they are known to be the most unbeatable performance/$ powerhead currently available. They are adjustable variable speed/pattern, DC powered so they're very efficient and best part is they can be controlled via reef controller, ie; reefangel or apex.
Yeah I was surprised with the purigen.Running some activated carbon will help keep the water clearer and help remove odors. I keep purigen and some carbon in my system usually without any problems. I'm not sure the purigen is terribly effective in SW. It takes a few months for mine to start getting even a hint of brown.
If you want crystal clear water you may want to start carbon dosing. Vinegar may be the best to start since you would need to add larger amounts and it's harder to overdose. Here's some information on carbon dosing:
http://www.reefaquarium.com/2012/carbon-dosing-in-laymans-terms/
I'll read more on the carbon dosing. I'll get some carbon for the sump this weekend and give that a shot.