Flow Help for Cube Tank

[azreefr]

Hello, I have been running two 6095's in my mixed reef 30x30x24in cube for the last 2 years. I've tried moving my power heads around in different configurations but I'm not able to balance the right amount of flow with the placement of the pumps. I've got ~25 SPS coral mid to high level, zoos and euphyllia at the lower level. I'm trying to keep the powerheads towards the back of the cube so they don't block the view.

Both 6095s are running at ~80%. I've been considering purchasing a Maxspect Gyre or an MP10 to get a wider flow. The 6095's have plenty of power. I just cant get the placement right. You guys are pretty sharp. Any suggestions on powerhead placement? Anybody use two powerheads to create a Gyre? Thanks.

 

[rvitko]

Are you alternating the pumps or are they both always on at 80%? Any chance of a photo?

 

[azreefr]

Tunze's current location in red.

 

[azreefr]

I'm running two profiles:

Day: Synch - Off, Divide by 10 - Off, Initial time - 0 sec, On time - 10 sec, Off time - 15 sec, min intensity - 30%, max - 80%.

Flush - Synch - on, Divide by 10 - On, Initial time - 0 sec, On time - 20 sec, Off time - 10 sec, min intensity - 30%, max - 95%.

I have ~ 100 gal system and I'm running with the 20V fuses (~33x turnover).

I couldn't keep the sand in place even after adding heavier crushed coral so I throttled down to the 20 V.

I know these pumps have a lot of flexibility. Any suggestions on the programming or placement would be appreciated.

 

[rvitko]

I don't really understand the programming profile, what I would suggest is something like our Interval 2 or Interval with Idle speed. One pump pulses for 5-6 hours at 30-x (whatever the highest speed you want to use is) and the other idles at 30%, after 5-6 hours they switch, this roughly mimics the tides and washing of waves. I think the placement is fine. I would primarily work with the programming and speeds. Rapid changes of direction of flow are not usually the best way to go, most research shows that corals deploy their polyps in the direction of flow to catch food and they learn the cycles and longer cycles are more natural and advantageous. Barring a storm, nature tends to have a fairly consistent rhythm. A storm flush once a week or so that is very brief can be a good idea, but I would keep the patterns steady and longer with flow in a given direction.

 

[azreefr]

Thanks Roger. For the pulse pump: How many seconds would you pulse and how many seconds would you sit at idle? For example 5 sec pulse then 30 sec idle, then 5 sec pulse?

 

[rvitko]

I would have one pump idle for 5-6 hours and the pump that is on pulse at intervals between 2-4 seconds. The interval between the pumps of 5-6 hours is to replicate the tides which will be the major change in nature of flow direction, the pulsing does two things, it simulates the washing effect of waves and you are colliding fast and slow bursts of water and the result is a wider flow. You want the bursts to be fast enough, but not too fast, too fast and the pumps don't get completely up or down to the set speed and too slow and the collisions are largely lost as the water will first reach the walls of the tank.