Flow in the tank

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I have 6 powerheads in my tank vary in flow rating running off a AM wave, so the flow is pretty random.

Is there any advantage to actually moving powerheads around the tank - different positions from time to time ? Creating a totally different flow pattern ?

I am doing coralline maintenance and was wondering if should start moving things around
 
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Hi Warr,

Interesting question, but unfortunately I must answer: "I don't know". We can speculate, though :whistling:

Even though the flow from the existing PH positions would be considered "random", I do think that there would be some kind of pattern to the water movement, just as there would be a pattern to the flow on the reef - varied but still repetitive...

Our larger invertebrates (corals, tube worms, clams, etc.) don't have much choice in where we place them in our tanks, but they will naturally adapt over the long term to whatever conditions (lights, flow, etc.) they are exposed to, if it does not kill them.

My "gut feeling" is this:
  • There will be some advantage to changing pump positions/water flow pattern if their original positions were less than optimal.
  • Doing this regularly might have benefits in e.g. causing the corals to grow more "normal" and not extend to (say) only one side, but it increases the risk of affecting the sessile inverts negatively due to the change in flow.
  • There would more likely be an over-all negative effect if the corals/inverts have been in the tank for long enough to start adapting to the particular flow-pattern they've been experiencing.
Let's hear what everyone else has to say ...

Hennie
 
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I agree 100 percent with the above statement. Well put
 

leslie hempel

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Hi Warr,

Interesting question, but unfortunately I must answer: "I don't know". We can speculate, though :whistling:

Even though the flow from the existing PH positions would be considered "random", I do think that there would be some kind of pattern to the water movement, just as there would be a pattern to the flow on the reef - varied but still repetitive...

Our larger invertebrates (corals, tube worms, clams, etc.) don't have much choice in where we place them in our tanks, but they will naturally adapt over the long term to whatever conditions (lights, flow, etc.) they are exposed to, if it does not kill them.


My "gut feeling" is this:
  • There will be some advantage to changing pump positions/water flow pattern if their original positions were less than optimal.
  • Doing this regularly might have benefits in e.g. causing the corals to grow more "normal" and not extend to (say) only one side, but it increases the risk of affecting the sessile inverts negatively due to the change in flow.
  • There would more likely be an over-all negative effect if the corals/inverts have been in the tank for long enough to start adapting to the particular flow-pattern they've been experiencing.
Let's hear what everyone else has to say ...

Hennie

i think that pretty much nailes it....other than tsunami action ;)
 
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The growth statment is something i am interested in. I have and have seen sticks that branch a certain way due to the flow. Chnage the flow pattern and the coral grows differently.

The reason I asked this question: Don't the natural reefs have seasonal changes in tides, thereby meaning change in flow pattern ?

Or is this seasonal change so minor that the flow pattern wouldn't really change ?

Another thing are aqua cultured corals/inverts stronger or weaker than their wild cousins ?
 
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In esence yes, aqua cultured corals are stronger ( i assume you mean more hardy ) than wild harvested specimens, especially where aquacultured specimens are purchased from fellow hobbyists. Naturally, the generation & age of a frag also has an influence on its survival rate. Think about it...... A frag from a 3rd generation aqua cultured coral ( parent fragged, then frag grown out and fragged then grown out and fragged again and given time to settle ) has survived through quite a substantial amount of hobbyists errors, equipment failures, shifts in parameters, power failures etc. Compared to a first generation frag, just off a wild colony, mounted given some time to adjust and then moved out. The parent and frag are both still trying to recover from the stresses of harvesting, shipping and surviving the dealer and hobbyists tanks.

Unfortunately, the livestock in SA shops are predominantly wild specimens, even when they appear to be aqua cultured. ( mounted on a cement base) Considering the origin of most corals entering the SA market, I can tell you with confidence these corals have been harvested from the wild. Snapping off a few twigs, mounting on a base and growing out on racks suspended in the ocean, is not aqua culture., and will not add much to the hardiness / survivability of a coral.

From wikipedia:
Aquacultured:
implies the cultivation of aquatic populations under controlled conditions.
Maricultured:
Mariculture is a specialized branch of aquaculture involving the cultivation of marine organisms.... and other products in the open ocean, an enclosed section of the ocean
 

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