Folks, if you've recently upgraded or renewed your annual club membership but it's still not active, please reach out to the BOD or a moderator. The PayPal system has a slight bug which it doesn't allow it to activate the account on it's own.
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If you don't need it right away wait for the next group buy. The Vortech would cost you $357. If you didn't like it you could still sell it and probably make some money. My Vortech is in a 46g tank dialed back but I'm ready for future upgrades. Noise wasn't an issue once the unit was...
The Vortechs don't transfer heat to the tank (motor outside of aquarium). I don't know what the max flow rate is for the Koralia but the Vortechs are 500 - 3000gph. Check out this video from MACNA.
http://www.youtube.com/watch?v=rLPmea2II-A
Bob