Can we talk FLOW?

[DmitryB]

Let's talk about FLOW! Flow is more difficult to figure out and set up than lighting. I mean with lights you buy a light with enough power for your set up, pick the light preset you like, and go. Pretty much plug and play. But not flow. Flow is a monster to tame. A million things to consider. Especially when Low, Moderate, and High are kind of meaningless terms. They can mean anything. As a lover of classical music I think of it as musical tempo markings. Andante will mean different things on a different day to a different conductor, which is why Beethoven's Fifth will sound different every time. So it is with Flow. How do you make everyone in the tank happy? Fish, but especially corals. This one wants low, that one wants high, that one is Goldilocks, doesn't know what it wants. And neither do we. Oh and then there's sand.

So how did you or do you figure out your flow? Do you acclimate your corals to flow as well as lighting? How long do you give a coral before you decide "This isn't the right place for it."

I'm currently trying to figure out flow of ray 170 gallon. I have two Orcas 6105 on the back corners + a ReefWave 45 sending a sheet of flow across the surface. (I'm ignoring the return.) I'm trying to decide how high to raise the Orcas. Do I create high flow in the upper half of the tank where SPSs will be located and leave the lower half Moderate/Low for Softies and LPS? How do you arrange your powerhead? What's the secret sauce to flow?

 

[KrisReef]

I don’t think there is a simple answer. As you noted, different corals want more or less water movement, while a pump or a return nozzle are somewhat limited in the output they produce.

Our ability to move water around a tank cannot compare (or replicate) the continuous water changes that coral on a reef experience.

Current in our tanks blows compared with natural situations that will corals experience.

I need to acid dip my gyre and wave makers today, something that nature doesn’t have to do to keep the water moving. The movement is key for respiratory function, for feeding and removing metabolic energy.

 

[Biokabe]

Flow is one of those things that, if you can really unlock it, I think it can do great things for your reef. But it's easy to overcomplicate it, it's easy to overengineer it, and it's easy to do it wrong.

For myself, I try to have a lot of random flow coming from different sources, and I use the rockwork to create areas of reduced flow for corals that like more peaceful flow. I don't know enough about flow to design the "perfect" flow for everything, so whenever I add a pump, I just figure out the max rate, select the "random" setting, and put it where I think it'll do well. I currently have four powerheads in my tank and flow seems to do well for everything, but time will tell.

 

[mfinn]

I'm currently trying to figure out flow of ray 170 gallon. I have two Orcas 6105 on the back corners + a ReefWave 45 sending a sheet of flow across the surface. (I'm ignoring the return.) I'm trying to decide how high to raise the Orcas. Do I create high flow in the upper half of the tank where SPSs will be located and leave the lower half Moderate/Low for Softies and LPS? How do you arrange your powerhead? What's the secret sauce to flow?

It sounds like you have the equipment in place to create a high surf zone everywhere. ( ignore the return is good)
It also sounds like you have formed a plan.
Go with your ideas and be willing to modify them based on results you see happening real time.
Only you with your rock placement and coral placement can really make the right call.
Picture in your mind how you want the water to flow. Flowing clockwise or counterclock wise, or just crashing into it's self in the middle.
Set the powerheads in the appropriate spots to make you plan work.

I don't have a specific answer except to try it one way, if that doesn't work be flexable.

 

[exnisstech]

Trial and error is all I've come up with. Sometimes I'll use coral snow or a heavy feeding of frozen to see how things blow around the tank and adjust if needed. I'm starting to lean toward too much flow vs too little as long as coral aren't being damaged or blown in the same direction all day.

 

[Mr. Mojo Rising]

I feel that good flow is key to a healthy tank, its not just for corals. I try to provide as much flow as possible without blowing sand around and not blowing corals off their skeletons. I think most people would cringe at how much flow my hammer and acan and other lps get.

The truth is you will never be able to keep every single coral happy, everyone has some type of coral they just can't keep alive. There's lots of alternatives so move on to something else.... just my opinion.

 

[DmitryB]

Flow is very tricky because everyone has to be happy! LOL

Here's a vide of my 170 gallon with coral food floating around. What would you say this is at various levels? The intent, of course, is high at top and low/moderate at bottom. But what those things mean is hard to gauge. Do you think the bottom of tank is moderate or low? Is top high or moderate?

The video is in 4K, so you should b able to get a good view of the coral food in that resolution.

 

[X-37B]

Flow is very tricky because everyone has to be happy! LOL

Here's a vide of my 170 gallon with coral food floating around. What would you say this is at various levels? The intent, of course, is high at top and low/moderate at bottom. But what those things mean is hard to gauge. Do you think the bottom of tank is moderate or low? Is top high or moderate?

The video is in 4K, so you should b able to get a good view of the coral food in that resolution.

Flow looks good.
In my ext 170 60×30×21 I run 2 sea sweeps with Tunze 6255's.
Plenty of flow with nothing else needed. I am not even at 50% after 2 years.
I can turn up the flow as it grows in.
I would go Orca 6105's If I was to start new.
I also run a sweep with a Jebao ow-40 in my ext 112.

 

[DmitryB]

Flow looks good.
In my ext 170 60×30×21 I run 2 sea sweeps with Tunze 6255's.
Plenty of flow with nothing else needed. I am not even at 50% after 2 years.
I can turn up the flow as it grows in.
I would go Orca 6105's If I was to start new.
I also run a sweep with a Jebao ow-40 in my ext 112.

Thanks! Is the flow at top "high" enough? I guess I can see once I start placing SPS and clams up there. (For now I have a small Biota clam only and it's only been in the tank 3 days, so acclimating to light.)

Orcas are great inventions (I wish the software worked better). Their rotations solve so many problems! And I wish the gyro wave makers like ReefWave were slimmer, but I'm sure in a few years someone will make a slim profile one. But that sheet of flow they send at the top is perfect for surface and Orcas spreading flow everywhere else. I am very low on Orca settings, no higher than about 50%. I have return nozzles posting to the back to get water behind rocks moving. Setting up Orcas to rotate to the back pushes too much water into the overflow at once and creates more draining noise than I like to hear every couple of minutes.

For my 40 gallon I'm running an MP 20 and a Nero 3, but I'm actually considering only putting in ReefWave 25 and sending one side to surface and one side slightly down. It'll send water in one circular direction, but that may be ok if they also run on reverse sometimes?

 

[Biff0rz]

I recently cleaned out my 2nd frag tank, dedicated it to sps, and upped the flow. I want to experiment with higher flow and see how the sps respond. So far, so good.

 

[Biff0rz]

Thanks! Is the flow at top "high" enough? I guess I can see once I start placing SPS and clams up there. (For now I have a small Biota clam only and it's only been in the tank 3 days, so acclimating to light.)

Orcas are great inventions (I wish the software worked better). Their rotations solve so many problems! And I wish the gyro wave makers like ReefWave were slimmer, but I'm sure in a few years someone will make a slim profile one. But that sheet of flow they send at the top is perfect for surface and Orcas spreading flow everywhere else. I am very low on Orca settings, no higher than about 50%. I have return nozzles posting to the back to get water behind rocks moving. Setting up Orcas to rotate to the back pushes too much water into the overflow at once and creates more draining noise than I like to hear every couple of minutes.

For my 40 gallon I'm running an MP 20 and a Nero 3, but I'm actually considering only putting in ReefWave 25 and sending one side to surface and one side slightly down. It'll send water in one circular direction, but that may be ok if they also run on reverse sometimes?

https://collectorscorals.com/collections/ocean-sea-wave