Quote:
Originally Posted by Delphinus
I always thought water velocity and the shape of the water flow / cone / whatever was the more important thing to get right. I've always kind of thought the "must have moar turnover" school of thought was kind of silly in much the same way it was silly to speak in terms of "watts per gallon" 15 years ago when we talked about lighting.
Your plan seems more or less legit to me. FWIW.
|
I'm totally with Tony on this one and that has been my experience over the past 5 years. When I started the tank I was told to get as much flow in there as possible. So to
start with I got two Tunze 6105s to blast the tank with flow with the intention to add more soon after (they're expensive buggers). Well, I never did end up getting any more beyond the original two 6105s.
When I first set up my 6105s I had the both on full blast to get the most out of them. A few months later I decided to play around with varying their speed and programming them with my controller. I ended up with a variable speed setup where one 6105 would run at 100% while the other one ramped down to only 10% flow, and they alternated this way back and forth. This generated some nice random swirly flow and things thrived for the first couple of years with this setup. As a result of this setup though, one tunze ended up not running at 100% at any given time so I effectively had cut my flow rate down from when they were both on at 100%. Anyway, things did just fine.
Early last year the programming cable on my powerheads died so I lost control of them from my profilux. I ended up having to run them both at 100%. I intended to replace the controller cable but never did. The only real change I noticed was that corals were growing in a certain direction (with the more directional flow). Also, corals that were closer to the powerheads were not as happy (less polyp extension). Then in the summer one of my tunzes completely died so I run on one 6105 all summer and fall. The result of this was a gyre whipping around my tank in one direction. I didn't really notice much of a change in the corals that I could attribute to the reduced flow (I had other bigger issues like a busted skimmer).
Anyway, so a couple of months ago I finally got around to redoing my flow by removing the one remaining 6105 and replacing it with toe jebao RW-8s. Each one having significant less flow than the 6105 (on paper anyway). I run these on a pulsating mode to simulate a gentle wave. What I've noticed with this flow pattern is that virtually everything has nice polyp extension (when they weren't being nipped on by my small angels) and seems to be quite happy. LPS, SPS, softies. I haven't seen my corals this healthy and happy since the earlier days of when I ran a more random flow pattern through the tank. This despite the fact that I'm currently running the lowest flow rate that I have ever ran through he tank.
So in 150g, I'm running two RW-8s that are in the magnitude of 2000gph each (but the don't run continuous, they pulse so I don't know what that means to the actual flow rate). Plus my mag 18 return pump which adds a little bit of flow. That gives you an idea of my flowrate.