Water Circulation Questions

[Quigley]

Thanks for your help!

My wife and I recently purchased a used 90g fish & live rock setup that we are converting to a reef tank. Our goal is that the tank would be able to grow a wide variety of corals. We've worked through a number of different projects and are now tackling water flow and circulation.

The tank has a gravity feed overflow in the middle, which feeds a 20g refug, into which sit 2 Mag 9.5 pumps. The pumps return water to the upper thank through 3 nozzles placed along the back of the tank. One pump drives 2 nozzles, and the other drive 1 with the water passing through a UV filter. Calculating in all the losses I estimate the water flow at roughly 1,400 gph. The nozzles have enough flow and force to dig large holes in the sand bed in the bottom of the tank.

I've read that a reef tank should circulate 9 to 10 times its volume per hour and that the water flow should significantly agitated the tank such that you avoid any "dead spot".

I believe our current setup meets these two criteria, but what other considerations are there? What else do we need to be concerned with in setting up water flow in this tank?

Merry Christmas,
Randy & Deanne

 

[Reefdaddy1]

A smooth wave action would be of help. Meaning a alternating current using powerheads and a controller. Tunze or Seio type would be ideal. That would be your only need as far as flow would go in my opinion.

 

[Krish]

Wave action like Bob stated is always best flow for a tank, but most people can only get away with good random flow which does the job as well. The main thing you'd want is complete coverage of the tank to avoid deadspots like you mentioned so that detritus won't settle on the rocks and fuel nuicance algae to grow. Also, you have to keep in mind that corals, un like fish, cannot search for food so it has to be brought to them via flow so you will need sufficient flow to bring their food to them. As for how much flow you need, with having a sand bed, it gets kinda tricky. You put too much and you have a sand storm, while at the same time you still may not get total coverage which is one of the reasons why I use bare bottom tanks. I've had my 38 gal turn over it's volume about 104 times per hour (almost 4,000 gph of flow) and my corals loved it, my fish even loved it, and I never had anything settling anywhere in the tank. I guess you'll have to play with it some as all tanks are different though. What I usually do is toss a small pinch of flakes in the tank and see where the flow takes it. If it stops anywhere, you know you're lacking in that area or if in certain areas the flow is too slow, you know what you need to do. Just a thought...Good luck

 

[roblou]

Hi Randy & Deanne: IMHO, 10x turnover per hour would be the minimum for overall tank flow...possibly not enough for many corals to thrive. Although I think 10x turnover through your overflow & return pump is probably pretty good, you may want to look to increase your total flow. As krish mentioned, generating flow as high as 100x turnover isn't uncommon. I believe you'll find most folks run fairly low flow through overflow (such as 10x), with the majority of the flow coming from either a closed-loop system or powerheads in the tank.

FWIW, I also have a 90g tank. I run around 10x flow through my sump, but in the display I have 2 seio 1100's and 2 maximod 1200s. Those 4 powerheads generate approx 6000gph, so my total turnover is around 70x per hour. I also run those powerheads on a seio controller, which helps create some randomness. I also have a SSB and don't have any problems with the flow making sandstorms.

hth,
rob

 

[Quigley]

Thanks everyone for your help!

It sounds like we need to increase the circulation in our tank. I've done some researching on powerheads and have several questions. Your patience in helping us learn is greatly appreciated.

- What brands of powerheads are known to be reliable and long lasting? Saio, Maximod, and Tunze have been mentioned, any others?

- How many powerheads, and what ghp, would be a good match for our 90g tank? (I'll attach pictures). We would to grow a wide range of corals.

- When you buy, say 4 powerheads, do you typically buy them all at the same gph?

- If a powerhead is advertised as providing appropriate flow for a 50g reef tank, does installing 2 of them make it appropriate for a 100g reef tank?

- What are some of the common places in the tank to mount the powerheads?

- I've read about powerhead controller; some are as simple as alternating on/off to the powerheads, and some much more complex. What functionality is needed in a powerhead controller?

Our tank is coming along. Our filtering is working well, we got our LR aquascaped with acrylic rods, we are very happy with our new MH/PC light, our water quality is steadily improving, and our fish smile more often now. We are hoping to start growing some corals by Christmas.

All this success is thanks to everyone's help!

Thank You, and Merry Christmas,
Randy & Deanne

 

[Krish]

Not sure if you've seen this thread yet, but this will give you some ideas as to what people are using in their tanks

http://www.reeffrontiers.com/forums/showthread.php?t=18140

As for your questions, let's see...

What brands of powerheads are known to be reliable and long lasting? Saio, Maximod, and Tunze have been mentioned, any others

I think you mentioned all the best. The only other great powerhead out there IMO is the Vortech that is great because the motor sits outside the tank which reduces heat and also takes up less space. http://www.premiumaquatics.com/Merc...OD&Product_Code=ICE-VORTECH&Category_Code=Eco I've never used one before, but love Tunzes and Seio's.

- How many powerheads, and what ghp, would be a good match for our 90g tank? (I'll attach pictures). We would to grow a wide range of corals.

Well, every tank is different, but when I had my 90 gal, I ran (2) Seio's first (both 820 gph) and it was a bit lacking so I went to (2) Tunzes (one @ 1600 gph and one @ 1850 gph on a controller) and it did the trick. My tank was bare bottom so I was able to put them anywhere, but here are 2 pics below of the 90 gal with the Seio's and then the Tunzes

- When you buy, say 4 powerheads, do you typically buy them all at the same gph?

Typically that's what people often do, but not necessary as you can see I used 2 different sized Tunzes and was happy with it.

What are some of the common places in the tank to mount the powerheads?

Powerheads can be mounted pretty much anywhere and a lot of the time people will mess with them constantly to find the "sweet spot" but how I had my Seio's in the first attachment and the Tunzes in the 3rd attachment (my old 75gal) is a good way to mount them. You get good random flow as the flow from each powerhead collides at the center point in the tank. I know a few people running powerheads like this and love it

- I've read about powerhead controller; some are as simple as alternating on/off to the powerheads, and some much more complex. What functionality is needed in a powerhead controller?

Typically what all powerheads (that run on controllers) try to accomplish is a wave action like you experience in the ocean. Some, like my Tunze that used the controller, would allowed you to adjust the flow at 2 different settings for a timed amount of time. What that meant was I had it set to put out 1850gph of flow for about 5 seconds and then the controller would switch it to only put out about 600 gph or so for 5 seconds and then back to the 1850 gph. Same theory behind the controllers that shut off and restart powerheads. You'd have one powerhead on one side of the tank blow full throttle and the opposing one on the other side of the tank would be off, then they'd switch, so what that would cause is basically a back and forth wave action like the ocean

Hope that helps some and I think your tank looks great!! Good luck on the extra flow

 

[reeftnk101]

The Seio pump with 2 1500's would be great.
Matt

 

[Quigley]

Thanks for the replies! I've followed up on all the links. Some great information.

We are considering purchasing 2- Tunze Turbelle Stream 6060 units. These are 1,585 gal/h, and cannot be used with a controller. We are thinking we would mount one on each side of our 90g tank and adjust for the sweet-spot. We would run these both during the day, and maybe only 1 or 0 at night.

Our "plan B" is the Tunze TS07 kit, which includes 1- 1,850 gal/h unit and the simple pulse controller.

What do you think? Advantages of one over the other?

Merry Christmas,
Randy & Deanne

 

[Krish]

For me personally, I liked the idea of having 2 tunzes in my 90 gal. I tried it with one at first (6060) and needed a bit more so I added another one (6010 kit) and I was happy afterwards, especially in a tank that tall. Not sure if the single one will do the trick for you because every tank is different, but just wanted to share my personal experience.

 

[Scooterman]

I think one problem with relying on just PH's is you will still have dead spots, more so when you add the LR. If you can reduce the spots to areas easily vacuumed then it should be ok.

 

[Quigley]

Two powerheads sounds like the ticket!

Has anyone ever tried a Tunze non-electronic powerhead with an on/off switching type of wave maker?

Merry Christmas,
Randy & Deanne

 

[DonW]

Two powerheads sounds like the ticket!

Has anyone ever tried a Tunze non-electronic powerhead with an on/off switching type of wave maker?

Merry Christmas,
Randy & Deanne

Not a good idea its pretty hard on the pumps. MJ's are the only ones that are good to do that with. I'm sure its hard on them also but they are cheap so you dont mind replacing one every now and again.

Don

 

[Krish]

I agree with Don...Alot of manufacturers don't recommend putting thier pumps on wave makers/timers like that

 

[Quigley]

Krish,

Since you have both a Tunze 6060 and 6010 Kit, I am hoping you can help me with two questions.

How significant is the pulse/vary-the-speed feature of your one Tunze unit hooked up to the controller, in over all water circulation?

Lastly, I am wondering if a pair of Tunze Nano Stream 6055 (1,453 gal/h) would be as suitable as a pair of 6060's in our 90g tank. I realize the 6055's are not yet available, but I'm wondering if there is anything about their design or style that is not suitable for a 90g reef tank.

Thanks for all your help! Trust you family is all feeling better.
Merry Christmas,
Randy & Deanne

 

[Krish]

How significant is the pulse/vary-the-speed feature of your one Tunze unit hooked up to the controller, in over all water circulation?

In all honesty, without 2 of them on controllers working in sync, I'd rather just have them run full blast. I bought the one with the controller to hopefully upgrade the other one to the same, but never got around to it. The speeds can be varied quite a bit, but without running 2 of them on controllers, like I said, IMO doesn't make much sense. However, if you can get 2 opposing Tunzes both on controllers with one blowing full throttle while the other one is on minimum flow and then they rotate will always be your best option. Wave action like the ocean is always best as we aim to try an mimic the ocean as much as possible. Ever seen the video clip of the tunze wave box in action??? If not, let me know and I'll find you a clip. That's what you want to see happen in a tank and you can basically do that with opposing tunzes on controllers

Lastly, I am wondering if a pair of Tunze Nano Stream 6055 (1,453 gal/h) would be as suitable as a pair of 6060's in our 90g tank. I realize the 6055's are not yet available, but I'm wondering if there is anything about their design or style that is not suitable for a 90g reef tank.

Hmm...Well, to be honest, I'm not sure what to say on that one. I have the smallest tunze nano stream (660 gph), but would need to try out the bigger ones to say if they'd match up to the 6060's. I know the 6060's pack some serious punch! and have a really broad opening to provide a wide stream of flow, but I have yet to see the opening on the bigger nano streams to see if they'd have as broad of a stream. I'm thinking the flow on the nano streams won't be as broad but more focused, but could be wrong and with a tank your size, you'd want the broadest flow for more coverage IMO

 

[Quigley]

Krish & Friends,

We appreciate all your help with our water circulation questions. And, have ordered 2 Tunze 6060's with sure grip magnet mounts. The parts should arrive in a few days. And we will then work to find the "sweet-spot" for placement in our tank.

Again, Thanks Everyone!

Next, will be to work on water temp. I'll do all the research I can, and would then appreciate everyone's help with the questions that arrise. Our home does not have air conditioning and I can see the tank temp rising beyond safe when the weather warms.

Merry Christmas,
Randy & Deanne

 

[Krish]

Good luck! Atleast you live in Idaho! If you lived in the Bahamas with no air condition you'd be in trouble