Poll: Laminar Flow vs. Turbulent Flow

[saltyfilmfolks]

I was just going to say the complete opposite lol, that the ocean currents usually provide laminar flow. I'm now curious if I'm missing something. What makes you say random turbulent flow?

I was going to say IMO, but it's fact not opinion. it depends where you are and what the coral is.

 

[Mandelstam]

I was going to say IMO, but it's fact not opinion. it depends where you are and what the coral is.

I think what I was thinking about was the massive unidirectional flows of ocean currents etc. They are not random and chaotic. But when the flow hits an obstacle it becomes random and turbulent.

I read that article you linked to, great read! One passage stuck in my head:
"Although turbulence is the desired end product of water movement, aquarists should be more focused on producing faster unidirectional flow."

 

[saltyfilmfolks]

I think what I was thinking about was the massive unidirectional flows of ocean currents etc. They are not random and chaotic. But when the flow hits an obstacle it becomes random and turbulent.

I read that article you linked to, great read! One passage stuck in my head:
"Although turbulence is the desired end product of water movement, aquarists should be more focused on producing faster unidirectional flow."

Are you on the upswell of a high reef with tidal surges and hard corals ? Or very very deep on the up swell looking at sea fans ?

Or in my tank watching shrooms blow acros the bottom. Lol.
I hated my shrooms for a long time.

 

[jsker]

Turbulent up top and laminar middle to bottom. 2 gyre's up top and 1 mp40 in the middle

 

[Vivid Creative Aquatics Verified Sponsor]

In our standard 125, mixed reef tank, we run a mixture of both types of flow. A pair of MP40s on either side set to reef crest create a strong semi-laminar flow which is then broken up by a 4 Random Flow Generator Nozzles on our return lines. This creates a laminar flow pattern when the pumps ramp and overcome the effect of the RFGs but is then turned into a more turbulent flow pattern when the MP40s ramp down.

 

[dbl]

Based on the comments thus far, I've added another option to the poll - A combination of both! Sounds like many are trying to accomplish a combination so I think it makes sense to add the option. Good discussion so far! Feel free to change your answer if needed.

 

[Ghxst]

Based on the comments thus far, I've added another option to the poll - A combination of both! Sounds like many are trying to accomplish a combination so I think it makes sense to add the option. Good discussion so far! Feel free to change your answer if needed.

I can answer now!!! Lol thanks

 

[saltyfilmfolks]

Based on the comments thus far, I've added another option to the poll - A combination of both! Sounds like many are trying to accomplish a combination so I think it makes sense to add the option. Good discussion so far! Feel free to change your answer if needed.

Great topic btw!!

 

[Brew12]

Based on the comments thus far, I've added another option to the poll - A combination of both! Sounds like many are trying to accomplish a combination so I think it makes sense to add the option. Good discussion so far! Feel free to change your answer if needed.

I'm strictly turbulent right now but the new system I'm putting together will be a combination.

I'll have a gyre on each end alternating in a long tidal swell type mode. I will have 2 MP40's on the back wall that will normally be at minimum speed but will ramp up a few times a day (at least at first) to provide some turbulence from a different direction.

 

[vlangel]

My seahorse tank is predominantly laminar for the sake of the ponies. As swimmers they are accomplished enough but don't have the endurance of other fish. Also they stay hitched to something a large amount of the time and if the flow is more predictable, they wont use all their energy trying to stay hitched.
All that said, I do have 1 rio 800 gph pointed at the floor in a dissenting direction from the other 2000 gph, to keep detritus in suspension longer.

 

[ca1ore]

I would say it's both. You go diving in places like Cozumel, for example, where drift diving is prevalent it's a lot if laminar flow. Versus places like Caymen where it's very much surge and turbulent flow. I think one has to be very careful about having laminar flow in the aquarium as it an easily tear the coral polyps. I very much target turbulent flow in my tanks.

 

[MnFish1]

Maybe the question is really do you have laminar or non-laminar flow. Because - its really impossible to answer (to me) - would a maxspect gyre - on one end of the tank which is creating waves and huge amounts of flow - off and on every several seconds laminar/turbulent or both? (I guess I said both) - but the rock work and the interaction with the return pump flow probably also creates turbulent.

 

[dbl]

...but the rock work and the interaction with the return pump flow probably also creates turbulent.

This mirrors my thoughts on the subject and I touched on it in an earlier comment. It's my opinion that even with laminar flow, it will more than likely become at least somewhat turbulent (or at least disrupted) at some point. It will interact with the rock work, the corals, the walls, and other flow sources in the display. Obviously this is dictated by the size of the aquarium and the amount of flow.

In my case, I have two Gyre's on the short ends of a 120g peninsula. If they were to both run in the same direction (meaning one running forward and the other in reverse) it would stay rather laminar strictly due to the amount of flow generated in a small aquarium. But I run them opposite of each other so the flows "bump" in to each other causing turbulence.

 

[Ramon Estevez]

Well I’ve always done multiple powerheads pointed in different directions. But after getting back in the hobby and doing some research really interested in wavemaker and pump controllers to cause some chaos in the flow.

 

[GoVols]

Since I added the smaller gyre along time ago:
I run a combination of both.

 

[Katrina71]

Turbulent up top and laminar middle to bottom. 2 gyre's up top and 1 mp40 in the middle

That is kinda what I'm looking to experiment with.

 

[jsker]

That is kinda what I'm looking to experiment with.

It keeps it pretty stirred up. I will say, I like the new gyre controller.

 

[Katrina71]

It keeps it pretty stirred up. I will say, I like the new gyre controller.

Thank you! Exactly my goal.

 

[sweat90lx]

I'm trying to move the turbulent flow back every 30 minutes

 

[brandon429]

Very good thread. Laminar vs random has pros and cons both ways, reefers are trained to think only random is best

Not so, depending on specifics. Laminar always beats random where gas exchange is critical. People who rebuild eutrophic lake systems experiencing high fish kills detest random flow for this very reason. Giant airstones as big as a suitcase are used vs a massive pump due to cost, efficiency and nothing turns over a lake better than a giant bubbler, not even fifteen extra random pumps could hang to one correctly placed air stack

Random beats laminar in terms of detritus control, pure laminar deposits it in certain habit areas whereas random keeps it distributed better hoping export systems will catch it before that cruddy sandbed does

Coral feed is best distributed randomly/ideally.

Mines all laminar. A bubbled reef bowl is laminar up and over, a most powerful pH supporter given safe ambient home co2 levels.


I think most large size reefs are ok on gas exchange given normal home co2 levels, random would be my choice for a system with normal evaporation and normal sizing.

This physicality is handy in power outages. Simple d battery bubblers will get one farther for oxygenation, owing to the rule of laminar v random, than UPS setups running pumps as backup unless you have a zillion MAH in the rig.

Take that same ups setup and run its output on bubblers, keep the fish alive twenty times longer due to less current draw and more efficiency, laminar always beats random where gas exchange is critical, and not by a small factor, a huge one I can't recall the math its online though