140 gallon reef flow design

[ebayes11]

I'm in the process of putting together a 140 gallon tank (4' x 2' x 28"). I flirted with a closed loop manifold or ocean's motions permutation, but after learning about the gyre flow, I've decided that that is what I want to replicate. However, I don't want to have a permanent uni-directional gyre - I want it to alternate after sustained intervals. In order to minimize power requirements and external noise I have decided to use either Tunze streams or Vortechs. My inclination right now is to go with Tunzes, but I'm not set on it. I have a few questions to this end:

- Is this possible to create using only two pumps (Tunze or Vortech)?
- Has anyone done something similar?
- Does one of the products (Tunze or Vortech) lend itself better to this project?
- Will only one pump be able to get the water mass moving quickly enough to generate the desired velocity? (The other pump operating at a low output until the direction changes)


This will certainly not be a conventional "gyre" tank, but the flow will be similar. My primary concern with this is that I will not able to generate the necessary flow velocity with only one pump running at a time.

Thoughts anyone?

 

[ronj]

i'm not familiar with the "gyre" principle.. can you explain??

 

[Krish]

I'm not familiar with the "gyre" flow or pricipal either, but I'd just like to toss in that if you go with the Tunzes that use the controller you can set your own alternating flow pattern as well as flow rate. What I mean by that is when I had mine, I had the Tunze set to put out about 800 gph or so for about 5 seconds and then it would switch to about 1850 gph for 5 seconds then switch back. So if you have a tunze on either end of the tank, you can have them alternate between the 2 to create a sort of back and forth wave action. Just a few thoughts...Guess we'll need to find out what this "gyre" principle is first

 

[ebayes11]

It stemmed from an advanced aquarist article:

http://www.advancedaquarist.com/2007/1/aafeature

It basically talks about using multiple point sources of water flow in conjunction, rather than in opposition to create laminar unidirectional circular flow. After a sustained period of flow in one direction (15 minutes, or whatever) the flow is reversed.

 

[kgross]

I'm not sure if you could do it in that large of a tank with just 2 pumps. But you can give it a try. I would suggest going with the vortechs, just because I believe they produce more flow than the tunzes. But just go with the largest pair of pumps you can. On the direction change, I would say you should make it around 6 hours cycles. It will take time for the all of the water to start moving and get up to speed, so each time you change directions it will take a long time for the water to stop and then start moving in the other direction.

Here would be my suggestion do you. Use one vortech and your return pump to create the gyre flow and keep both running full speed to keep all the water moving. Then use the second vortech or a small tunze setup near the front of the tank moving in the opposite direction creating the turbulence The gyre will not change directions, but you will still have good random movement in the front of the tank. For this pump, have it go from as low of a flow or zero flow if possible to a medium flow rate, With like 10 minutes zero flow, 2 minutes medium flow 10 minutes zero. That way you keep the gyre flow going.

Kim
.

 

[freetareef]

nice idea... to throw in some turbulace every now and then.