JohnV8r
New member
I need some advice please. Here's the situation: I have a 175 gallon custom tank. Dimensions are 48"L x 30"H x 28"D. I have an ATB 1500 return pump connected to a Seaswirl that rotates the flow 90 degrees. With approximately 5' of head pressure on the return and a tee + gate valves that supply flow to my GFO and refugium, I estimate the actual GPH on the return at about 1000 GPH.
Here's the rock stack, etc, before I had added any corals to help you visualize my flow question.
There is now additional live rock on the left side where the Duncans colony is that extends to the protrusion just before the cave at about the mid point of the rock stack. I also have live rock on the front right section as well. These live rock sections were added to reduce the ongoing redistribution of the coral gravel that you can see from the wave-like patterns on the right side and front glass. Don't ask why I used sugar fine coral gravel - I was talked into it and will never make that mistake again.
The flow from the Seaswirl creates great turbulence from left to right across the top/surface, then down the right side, and then from right to left across the bottom 25% of the tank. I would describe this flow pattern as "high flow." The bottom left 25% of the tank and left-most side of the rock stack receives the lightest amount of flow of the tank and is where my low flow chalices, cyphastrea, and duncans like to be.
My questions really pertain to the middle section of the rock stack from above the 25" line to the 14" line. I would describe this area as a "moderate flow" area that receives a decent amount of updraft current as the Seaswirl rotates across the front glass and sends flow down the glass and up the face of the rock stack. All of my SPS frags in this area have good polyp extension and generally seem to be doing OK. However every time I go into an LFS and look at their frag tank, their SPS frags are practically vibrating from the amount of flow they are receiving. I always walk away thinking my SPS can't be getting half of the amount of flow the LFS frags are getting.
Because of this, I am considering adding a powerhead that would essentially create a left to right flow across the rock stack around the 20" line. Here then are my questions:
1. Do I need the additional flow?
2. How much flow should I add if I add any at all? For example since I would be adding supplemental flow, do I need need to add 200 GPH to the 48" left to right throw? 800 GPH, 1500 GPH, 3000 GPH...?
3. Would I be better off with a constant on flow or an interrupted flow from a wave maker control (e.g. on 5 seconds, off 5 seconds)?
Thanks in advance for your input!
Here's the rock stack, etc, before I had added any corals to help you visualize my flow question.
There is now additional live rock on the left side where the Duncans colony is that extends to the protrusion just before the cave at about the mid point of the rock stack. I also have live rock on the front right section as well. These live rock sections were added to reduce the ongoing redistribution of the coral gravel that you can see from the wave-like patterns on the right side and front glass. Don't ask why I used sugar fine coral gravel - I was talked into it and will never make that mistake again.
The flow from the Seaswirl creates great turbulence from left to right across the top/surface, then down the right side, and then from right to left across the bottom 25% of the tank. I would describe this flow pattern as "high flow." The bottom left 25% of the tank and left-most side of the rock stack receives the lightest amount of flow of the tank and is where my low flow chalices, cyphastrea, and duncans like to be.
My questions really pertain to the middle section of the rock stack from above the 25" line to the 14" line. I would describe this area as a "moderate flow" area that receives a decent amount of updraft current as the Seaswirl rotates across the front glass and sends flow down the glass and up the face of the rock stack. All of my SPS frags in this area have good polyp extension and generally seem to be doing OK. However every time I go into an LFS and look at their frag tank, their SPS frags are practically vibrating from the amount of flow they are receiving. I always walk away thinking my SPS can't be getting half of the amount of flow the LFS frags are getting.
Because of this, I am considering adding a powerhead that would essentially create a left to right flow across the rock stack around the 20" line. Here then are my questions:
1. Do I need the additional flow?
2. How much flow should I add if I add any at all? For example since I would be adding supplemental flow, do I need need to add 200 GPH to the 48" left to right throw? 800 GPH, 1500 GPH, 3000 GPH...?
3. Would I be better off with a constant on flow or an interrupted flow from a wave maker control (e.g. on 5 seconds, off 5 seconds)?
Thanks in advance for your input!
