Equipment/Pumps/Circulation  - 4/24/2006
Hello to all,  <Hello Elvis>   
Elvis here, trying to mentally prepare myself for the investment.  As I have never been a killer of life I surely don't want to start now.  I've read for months and will continue to do so.  This site is simply an incredible display of benefaction.  Thank you all.  <Thank you.>   
I'm setting up a 150 gallon tall; 48x24x30.  Gear I'm planning on purchasing are the Outer Orbit MH lighting system for the 48", an Aqua C EV180,  the Typhoon III RO/DI unit, a fully set-up quarantine tank (10-15 gallon).  Now to the question; pumps.
I'm tracking down information on the Oase Aquarius 4000/5000 ES pumps.  I seen the incredible performance/watt curves of these pumps.  But hard to find ones rated for saltwater.  If I go this direction I'll need to split the flow between the skimmer and the overflow returns.  With a gate valve between the pump and the skimmer should I be able to tune the flow for proper skimmer function?  Or should I have separate pumps?  <I don't believe Oase makes a saltwater safe pump.  Their pumps are
geared for koi ponds/water gardens, etc.  It is better to have a separate pump for the skimmer and sump.>   
What I was planning on doing was running two smaller pumps, maybe Oase, Eheim, Dolphin DP800.  Since the skimmer can only handle 600 - 700 gph, I was only planning on having a pump that would return that much from the sump.  The rest of the tank circulation would come from two Turbelles.  Logic was lower power consumption, lower heat imparted to the aquarium water, and about 3500 gph of circulation not including the sump return. <The Turbelles are an excellent choice and a trouble free, long lasting pump.  I think 3500gph is a little overkill in your system.  Somewhere between 1600-2000gph would work well.>   
I've read the wonderful things about the Tunze Turbelles.  I've read the wonderful things about closed loops.  Is it simply consumer preference that dictates why one get's used and the other doesn't?  <Aesthetics is one reason for using closed loop circulation, no pumps are in the viewing window.  Another reason is tank depth.  With the powerheads placed at water level, not much circulation will take place at the lower levels.  I personally do not like bulkhead fittings that far below the
water level, always a slight chance for a leak.  In your case, with a 30" deep tank, one pump should be placed in the bottom third of the tank.  I think you would be better off with four smaller Turbelles and run the system with a wavemaker.> The Turbelles are expensive, but not so much more that a Dart/Sequence pump.  The energy consumption, or lack of it, is swaying me to the Turbelles.  I've been in the chat rooms and everyone seems to like them.  <They are a good pump.> The same everyone also seems to be running closed loops with monster pumps.  I'm getting confused about the "best" circulation method.
<It really doesn't matter how you circulate as long as you are circulating 15-20X tank volume.  My suggestion, two Turbelles in the lower level and two at the upper level controlled by a wavemaker.  Aquarium Systems makes a very affordable wavemaker somewhere in the $50-60 range.  If you decide on a wavemaker, pump size can be increased as no more than two pumps will be on at the same time.  I use one and it works great.>   
A lot of what I keep seeing is people drilling huge holes in their tanks to run thousands of gallons of water through there sumps with huge, loud, power hog pumps and I can't figure out why.  What is in the sumps that's helping the water?  <A sump is an excellent place for gas/air exchange with the water, and oxygen is at near saturation levels, but overkill isn't necessary, just adding more heat and power usage for unnecessary circulation.>
Thank you again for all your time and effort.
<You're welcome.  James (Salty Dog)>   
  Elvis