Let's talk about perfecting water flow in a reef tank!

[Daniel@R2R]

Figuring out how to perfect water flow in your tank can be a challenge!! You're trying to find the best flow patterns & rates, pump placement, meet coral needs, not stir up the sand bed (but keep food suspended in the water column), eliminate dead spots, consider aquascape patterns and obstructions, and that's just getting started. Then as coral grows or as other changes occur, it's a rinse and repeat process. So today let's talk about tips for perfecting the water flow in your reef tank! Here are a few questions to help get us going:

1) What are some helpful tips/practices you put into practice when trying to figure out how to plan for flow in a reef tank? (Please include flow rates, placement tips, ...anything you think is helpful)
2) What are some of the biggest frustrations when trying to figure out flow in a reef tank? (What are some of the struggles that you're maybe even hoping others might address)
3) What is your process for troubleshooting flow issues in a tank?

 

[Peace River]

It would be great if there were a flow simulation for our tanks or we could add the little balls into our tanks like Sicce puts in their display tanks at reef shows (only these would dissipate or turn into food or beneficial organisms). Without those yet-to-be-provided items, I usually rely on watching the fish or corals as well as seeing where the food and waste settles.

 

[Daniel@R2R]

BUMP for reef flow talk!

 

[Kathy Floyd]

Interested to see some feedback on this.
The struggle is real. Lol

 

[Reefer Matt]

I regularly trim my sps coral because of flow problems after a while. Once a tank is full, there is nowhere for water to move. Too bad there isn't a portable flow meter available. Kinda like a par meter, but for flow.

 

[asome_one]

Just add a bubbler nearby whatever pumps you want to see the flow of. I discovered this because of annoying microbubbles I had when breaking in my skimmer. Shine a flashlight in the same direction as the flow with the bubbles and they light up like crazy. - at night - with the lights off that is.

 

[twentyleagues]

I am typically like @Peace River I see where dead spots are like where detritus build up or where food settles. I also watch the fish and see if any spots blow them around. I try to balance the two out. When setting up a new tank I kind of use the jedi approach or its just a feeling that what im doing wont cause to many issues.

 

[nothing_fancy]

IMO all dependent on shape and size of tank and scape, forgive me if that's obvious. I will say tho, for me, multiple flow sources at low energy have worked best for my setup right now (40g cube) I have (2) Mp10s maxing out at 70% set to reef crest most of the day and they are linked. Id say they average at around 50%. Those are left-right heads. Due to the lack of depth to the back wall I have the scape setup about an inch off the back wall. I setup a third mp10 Low in the far right corner below the scape running on its own program at about 30% otherwise I would have a dead zone back there. On the opposite corner about 1" off the bed is a Jebao SLW10 running random at 50%. Lastly the VCA random flows on the return with the reef oct running at about 50%. For me this keeps the more cryptic zones of the tank, the areas mostly behind the scape and in the caves flowing, very little to no algae and so far no problems with detritus build up. The flow at these rates isn't too much to keep inverts and fish out of their hiding spots and it isn't too little to provide a nice random flow within the tank overall. So long story short, more pumps scattered around with the majority set to Low energy.

 

[Daniel@R2R]

Too bad there isn't a portable flow meter available. Kinda like a par meter, but for flow.

Dude! I've honestly wished so many times that someone would come up with something like this!

 

[Reefer Matt]

Dude! I've honestly wished so many times that someone would come up with something like this!

It shouldn't be too hard to make. Just need a high enough demand. It would at least get us one more step to consistency and stability.

 

[Sisterlimonpot]

This is something that I recently trained my sights on. I was looking at an sps frag that I put in the tank 2 weeks ago, and noticed that there are now multiple 1/2" to 3//4" branches that a sprung up in those 2 weeks.

It's hard to say why, I lean towards flow because it was placed on the side of the tank in indirect heavy flow from the vortechs and neros.

Back to the thread: I personally change up my flow throughout the day. The majority of the day the 4 mp60s (2 each on the side panels facing inwards) are programmed in gyre mode, they swirl the water clockwise and then counter clockwise for 2 minute intervals for half the day then I switch up the sync/anti-sync so that its 2 pumps on one side push for 30 seconds and the other side pushes for 30 seconds. In the evening I get them to make a standing wave, then after lights out it goes into nutrient transport, then reefcrest until lights on.

Not that this is a schedule to follow, except the take away should be that randomly changing flow seems to be extremely valuable with coral growth and health.

 

[Peace River]

Good feedback @Sisterlimonpot! Another approach to regularly changing flow, is regularly moving the corals in and out of the flow like @TheHarold’s coral carousel.

 

[SPS2020]

It would be great if there were a flow simulation for our tanks or we could add the little balls into our tanks like Sicce puts in their display tanks at reef shows (only these would dissipate or turn into food or beneficial organisms). Without those yet-to-be-provided items, I usually rely on watching the fish or corals as well as seeing where the food and waste settles.

Red Sea AB+ works well for this (IMO).

I'm really happy with the flow in my tank which I partially attribute to the bare bottom and minimal aquascape. Two Red Sea ReefWave 45's on the back wall and an MP40 on the bottom right keep almost all detritus in the water column.

 

[Peace River]

Red Sea AB+ works well for this (IMO).

I'm really happy with the flow in my tank which I partially attribute to the bare bottom and minimal aquascape. Two Red Sea ReefWave 45's on the back wall and an MP40 on the bottom right keep almost all detritus in the water column.

Good call out! Yes, I have used that before as well!

 

[Dbichler]

I try to use powerheads for hitting my rocks two from the side of the tank and two from the back and use my four returns for the water columns. I use as much flow as possible even with only soft corals.

 

[Cool Fish]

It would be great if there were a flow simulation for our tanks or we could add the little balls into our tanks like Sicce puts in their display tanks at reef shows (only these would dissipate or turn into food or beneficial organisms). Without those yet-to-be-provided items, I usually rely on watching the fish or corals as well as seeing where the food and waste settles.

I agree. So, short of putting the little balls into our tanks, and looking at the corals, how can we best measure what our flow actually looks like in the tank? In frustration to see where my strongest flow was I put a piece of ribbon on a siphon tube and stuck in various parts of the tank to see how the ribbon extended and how strong the flow actually was. It was better than nothing, but not by much. It would be helpful to know what actual flow in different areas of the tank are. But hard to measure.

 

[Peace River]

I agree. So, short of putting the little balls into our tanks, and looking at the corals, how can we best measure what our flow actually looks like in the tank? In frustration to see where my strongest flow was I put a piece of ribbon on a siphon tube and stuck in various parts of the tank to see how the ribbon extended and how strong the flow actually was. It was better than nothing, but not by much. It would be helpful to know what actual flow in different areas of the tank are. But hard to measure.

As @SPS2020 suggested above, you can use Red Sea Reef Energy AB+ which is a fluorescent additive and it will give you a sense of the flow in your tank. Previously, I would use flake food to put in the current flow within my tank and see where it ended up. And yes, I have also done the ribbon thing in my tank. All of these options are hard to get a solid measurement, but they are ways to get a general sense.

 

[blaxsun]

This is the schedule I use for my pair of ReefWave45 gyres (positioned about 3.5" down on either side of the tank, facing inwards). The numbers on each wave type are the forward/back. These alternate between 8min forward and 2min in reverse.

 

[ArachnoJoozt]

Red Sea AB+ works well for this (IMO).

I'm really happy with the flow in my tank which I partially attribute to the bare bottom and minimal aquascape. Two Red Sea ReefWave 45's on the back wall and an MP40 on the bottom right keep almost all detritus in the water column.

Coral Snow is also a good way of seeing the flow patterns in the tank

 

[lakai]

SPS just go full blast nutrient transport mode 18 hours a day.