Current flow cycles???

[Lance]

Sorry i mean the skimmer doesnt collect very well and then disolved solids could raise. Well a return pump thats rated 800 gph at 5 feet would give the desired results. Please dont use a pump rated at 100 gph as this would not work. Then the sump is a tool used for water quality and not for added flow to your main tank. If your getting 600 gph through the sump alone this would be to much.


I've heard that too much flow is a problem. Is that true?
In the past, many hobbyists purchased huge energy-demanding pumps to push water into their display tank and create tons of flow. Their goal was to use the return pump as the main flow in the aquarium so they didn't have to look at any powerheads in their display. While that sounds nice in theory, it doesn't work well for several reasons. The main reason is microbubbles. I've seen big, long sumps with a series of baffles and sponge blocks used to help fight those tiny bubbles and avoid the eyesore of white bubbles blowing all around their reef tank.
For years aquarists have set guidelines about how much flow a reef tank needs based upon the types of corals kept in it, but that flow rate has nothing to do with the water passing through the sump. If the sump is very small, a very slow return pump is best. If the sump is larger, it is possible to use a bigger pump and still have no problems. The general rule I recommend is to multiply the display tank’s volume by three or five, and get a pump that matches that number. If the display tank holds 100 gallons, a 500gph return pump is sufficient. If the aquarist puts a 40-gallon sump under that tank, 500gph flowing through it should be trouble-free.

Reefkeeping 101 – Sumps! by Marc Levenson - Reefkeeping.com

He should be running at least 600 gph through the sump, although 700 to 800 gph would be better. The idea of 100 gph, or even 300 gph, through the sump with a 125-gal tank makes no sense at all.

I don't even understand what you mean when you say the water can't collect. What does that mean? Collect?

[Ninong]

Sorry i mean the skimmer doesnt collect very well and then disolved solids could raise.

Lance, your statement still makes no sense whatsoever. The rate of flow through the sump has nothing to do with the rate of flow through the skimmer. In my setup for my 120-gal tank with 22-gal sump, I used a Little Giant 4MDQSC rated at 1325 gph @ 1-ft head as my system return pump. It delivered ~1100 gph to my tank (it's rated 1080 gph @ 6-ft head). My skimmer required a Little Giant 3MDQSC rated at 1100 gph @ 1-ft head. Anything less than that and the skimmer would not operate properly.

The rate of flow through the skimmer depends on the type of skimmer but all of them certainly require more than you seem to realize, unless it's a miniature skimmer for a 20-gal nano tank. The rate of flow through the sump should be between 5 to 10 times the net water volume of the system. Anything less than 5 times volume is really inadequate. The 10 times number was considered the rule of thumb for SPS dominated tanks back before the really high-volume Tunze streams, etc., came on the market and before people started adding closed loop systems.

If someone has a closed loop system and/or some of the really high-volume powerheads (e.g., Tunze Stream), then water movement in the 5x range through the sump would be adequate but somewhat higher volume would be even better.

Well a return pump thats rated 800 gph at 5 feet would give the desired results. Please dont use a pump rated at 100 gph as this would not work. Then the sump is a tool used for water quality and not for added flow to your main tank. If your getting 600 gph through the sump alone this would be to much.

Lance, telling him that 600 gph through the sump alone would be too much is utter nonsense. You really don't have any idea what you're talking about. For starters, his sump should be sized appropriately for the size of his tank. So you can forget about melev's cautions about water flow through an undersized sump.

I've heard that too much flow is a problem. Is that true?

Too much flow could be a problem if you go nuts with it or if your sump is way too small in the first place.

In the past, many hobbyists purchased huge energy-demanding pumps to push water into their display tank and create tons of flow. Their goal was to use the return pump as the main flow in the aquarium so they didn't have to look at any powerheads in their display. While that sounds nice in theory, it doesn't work well for several reasons. The main reason is microbubbles. I've seen big, long sumps with a series of baffles and sponge blocks used to help fight those tiny bubbles and avoid the eyesore of white bubbles blowing all around their reef tank.

What Marc is talking about here are people who tried to run 3000 gph through a 40-gal sump. You get too much turbulence and noise, among other problems. That was back before closed loops were popular and before the invention of the Tunze Streams and subsequent knockoffs.

For years aquarists have set guidelines about how much flow a reef tank needs based upon the types of corals kept in it, but that flow rate has nothing to do with the water passing through the sump.

He's correct. The total flow in the tank is what's important for SPS. It doesn't matter whether it's 1,000 gph through the sump and another 1,500 gph through a Tunze Stream or 2500 gph through the sump. You still need a reasonable amount of the system's water volume per hour through the sump for various reasons (which I'm not going to go into here) but you can still add up all of your flow to come up with your total water movement inside the tank.

If the sump is very small, a very slow return pump is best.

No, getting a bigger sump is best.

If the sump is larger, it is possible to use a bigger pump and still have no problems. The general rule I recommend is to multiply the display tank’s volume by three or five, and get a pump that matches that number.

Yes, a pump that can deliver five times the net water volume in the system would be sufficient. I wouldn't drop much lower than that if you intend keeping mainly SPS.

If the display tank holds 100 gallons, a 500gph return pump is sufficient. If the aquarist puts a 40-gallon sump under that tank, 500gph flowing through it should be trouble-free.

He's not being clear enough in this recommendation. I can see now where some newbies could be confused. What he should have said instead of "a 500gph return pump," is a pump capable of delivering 500 gph to the tank after allowing for head loss. Some people may have only 4-ft head and others may have 7-ft head, so the pump has to be sized accordingly. A 120-gal tank holds less than 100 net gallons of water after you deduct for the thickness of the glass, the distance between the surface and the top of the tank, the volume occupied by the live rock and sand bed, etc. In my 120-gal tank with 22-gal sump, my net water volume was approximately 105 gallons total. The sump runs half-full so that's only 11 gallons there. The live rock actually displaces a lot less water volume than you might imagine. In the beginning, I had about 160 pounds of live rock and it displaced only about 14 gallons of water. And yes, I actually measured it.

Marc is recommending 3 to 5 times water volume per hour through the sump. I'm saying that 5 times is better if you intend keeping any SPS at all (regardless of the total water movement provided by powerheads). You could get by with 3 times volume through the sump if your system is mainly non-SPS and if you have adequate supplemental water movement via powerheads or closed loop. If you're running mainly SPS, there is absolutely nothing wrong with going for 10 times movement through the sump but just make sure your sump is large enough to handle it.

[zhenya]

OK, before this thread gets totally derailed I figured I would post again the original question by the originator of this here thread...
So, lets answer Doodaa's original question about flow patterns.
I always aim at having enough water flow through out the tank by whatever means necessary. Be it power heads, or some fancy return manifolds...don't matter. You need to try with your return nozzles ( you need to tell us what those are exactly) different positions, like maybe deflecting off of front pane of glass, or some rock work, or both. SCWD is not a bad way to simulate waves but it needs a strong pump(at least 1200gph) and it needs cleaning on a regular basis.
Inevitably, though, you still get detritus accumulating somewhere and some power heads aimed at those areas will help to keep it in suspension long enough for skimmer(or other filtering device to take some of it out) to take some of it out. Even then, there is no way to take all of it out just by skimmer and/or other filtration devices. However, this another matter and it doesn't fit in the scope of this discussion.
In my own, sps dominated tank which is 75g, I use quiet one 4000 pump rated at little over a 1000g for return through my 30g sump, and I also have 4 power heads to generate random flow through the tank. Two of them are on the wave maker and two Korallia3 pumps are just on all the time. My return nozzle from the sump is aimed at the apposite glass pane and hence the flow from it I would consider circular. Flow from the power heads is colliding and more chaotic, which works great for me as I see polyps waving everywhere.

One sure way to determine flow patterns is to try the pump without any rock work in place and put something light weight in the tank tied to a small rocks or rods(like ribbons, for example) and see how those things move. You can then adjust your nozzles as needed and perhaps repeat the test with the reef structure completed.

And I totally agree with Ninong on the flow rates through the sump...if your sump isn't big enough to accept flow-through needed for the size of the tank, get a bigger sump.

I'm currently upgrading my return pump and am contemplating how to set up the return nozzles. I bought a 1" SCWD and a Pan World 150PS pump to switch the flow around a bit.

I can't seem to find on this forum a suggested water flow pattern. Is there a preferred flow pattern? Circular one way, then the other, total chaos, or what? I know whatever I have planned will probably change due to aquascaping and such to make sure everything gets some flow...I'm just curious about general flow cycles and what experienced people have to say about them.

Thanks

[Lance]

Any size sump or fuge is better then none at all. So if he cant afford some fancy large setup then dont bother. Well i say bother. Some fuges can be very cool and can only help. Return pump is relivent to the size of course.
All the info i left was from a reefkeeping article and i believe i left a link. I have another link if you want. Not trying to disrepect at all but do you have any links or articles backing your claim that high flow through a sump works just as well as lower flow. You make it sound like im just typing nonsense here but im not. Im only going by my sources and if im mis informed then please inform me with more then your opinion alone. If im wrong i want to know. Teach me.......

[Ninong]

Any size sump or fuge is better then none at all.

Not true. If the sump is too small, it's worse than no sump at all because it could overflow in a power outage. The sump should be properly sized from the beginning. It needs to be large enough so that it can easily handle the overflow if the power goes off.

So if he cant afford some fancy large setup then dont bother.

That's a sarcastic comment.

Well i say bother.

You have an attitude problem.

All the info i left was from a reefkeeping article and i believe i left a link.

You left a link to an article on sumps by melev (Marc Levenson). Marc wrote that article for Reefkeeping. He took over as editor of Reefkeeping after Skipper got tired of it. Marc is a fellow hobbyist. I remember when he upgraded from his 55-gal tank to a 280-gal tank three years ago. He got a very good deal on a used Starphire tank (72x30x30). If you go back to the sump article, the photo at the very bottom is a picture of the new 150-gal sump Marc made for his 280-gal tank. That's the black back of the 280-gal tank in the picture.

Mark wrote an article on sumps and included a photo of his sump that he made. Mark makes and sells sumps. If you want one, you can contact him.

I have another link if you want. Not trying to disrepect at all but do you have any links or articles backing your claim that high flow through a sump works just as well as lower flow.

You're twisting things around. Nobody said anything about "high" flow. High flow happens to be fine as long as you can control it. I have suggested that it's too much trouble to go for high flow. You're better off with moderate flow. What I consider moderate flow most SPS enthusiasts consider low flow. I'm suggesting a range of five to ten times the total water volume through the sump. Five times would be a minimum, as far as I'm concerned.

Marc seems to be suggesting in his article that three to five times the water volume would be an acceptable minimum. I'm saying five times is a good minimum. BTW, according to Marc's website, he's using a Little Giant OPWG-46 as his system return pump. According to this link, which I got from Marc's website, that pump is rated at 46 gpm (2760 gph) @ 5-ft head (which is why it has 46 in the model number). So, according to Marc's website, he is running a pump rated at 2,760 gph on his 280-gal tank. His sump is 150 gallons. If you figure 230 gallons for the tank and 70 gallons for the sump, he has approximately 300 gallons of water net in his system. So he's running nine times his net water volume through his sump according to his own website.

You make it sound like im just typing nonsense here but im not.

On the contrary, you actually are typing nonsense. You suggested 100-300 gph through the sump for his 125-gal tank. That's ridiculous. It's nonsense. It's terrible advice. You then told him that 600 gph through the sump would be too much flow. It isn't too much flow. You seem to be basing that on something you think you read, possibly from the article melev wrote about sumps, now that he is the editor of Reefkeeping. There is nothing in that article to suggest that 600 gph would be too much flow through the sump for a 125-gal tank. Certainly Marc has no problem himself with running high flow through the sump on his own tank. I recommend 5x to 10x and Marc is running 9x. I know some hobbyists who are running more than 20x through the sump but that can be really difficult to manage for several reasons.

Im only going by my sources and if im mis informed then please inform me with more then your opinion alone. If im wrong i want to know. Teach me.......

Well, you're not going to get more than our opinion alone (mine and Gene's). Maybe we'll write an article and publish it in our in-house magazine. Then you can link to that.

[Lance]

Like i stated , i mean no disrespect. I only want to help. All i did was backup my reply with an informative link.
Any size sump could overflow , its all about the setup.
If you have a constant 600 gph passing by any equipment in the sump then its not going to work very well.

But ill stop. As you dont understand.
Sorry if i caused any problems on this thread.

[Ninong]

If you have a constant 600 gph passing by any equipment in the sump then its not going to work very well.

That's not true. In fact, it's absurd! It's the dumbest thing I have ever read.

But ill stop. As you dont understand.

Of course I understand. You're the one who doesn't understand and you have no clue what you're talking about.

Sorry if i caused any problems on this thread.

The problem that you have caused is that you have given incorrect, even ridiculous advice and you have refused to accept the fact that you are wrong.

You are wrong. It's a pity that you don't see that.

[Lance]

Are you 12. I gave good info with a relyable source in the form of a link. All you do is ramble on with nothing to back up your reason for thinking i typed the dumbest thing you ever heard. Just one link and i might reconsider.

[Ninong]

Are you 12.

No, I'm 17.

I gave good info with a relyable source in the form of a link.

You did NOT give "good info." There is nothing in Marc Levenson's article that would suggest that "100-300 gph" would be a good recommendation for someone with a 125-gal tank. There is nothing in his article to suggest that "600 gph would be too much flow" in his situation. Your statement that "if you have a constant 600 gph passing by any equipment in the sump then it's not going to work very well" is ridiculous. Where did you get that idea? The "equipment" in the sump is not affected by the rate of flow of the water through the sump. The skimmer pump draws water from the sump to operate the skimmer. It pumps at the same constant rate no matter whether the water flow through the sump is 600 gph or 2,000 gph. Your comments in this thread reflect a lack of understanding of basic fundamentals.

All you do is ramble on with nothing to back up your reason for thinking i typed the dumbest thing you ever heard. Just one link and i might reconsider.

I don't have to "back up" my comments. I know what I'm talking about. You're the one who has no clue. I suggest you continue your research.

[Doodaa]

Thank you Zhenya (and others) for your advice. I didn't mean to stir up a big debate although it is informative I didn't know if a switching circular type of flow pattern was prefered over a "stuff blowing everywhere" type of pattern. I thought maybe it didn't matter but I'm am certainly not even close to being experienced at all. Seems to me in the wild that it would be mostly pretty turbulent with no consistent flow pattern. I was mainly asking if it really mattered. Will it affect their growth, make them healthier, etc...or is it just "flow" that matters and nobody is concerned with what type of pattern it is. Does just changing it once in a while make the difference it takes?

I see Lance's logic with what he's saying...keep the water in the sump longer for the equipment to process it more. I think Lance is getting at the sump water will be "cleaner" than the display tank water and will pump "clean" water back to the display. Makes sense, but in reality the skimmer will work better or more efficiently with dirtier water so the higher flow rates that Ninong is recommending would be better. Also, depending on the equipment in the sump, you'd want all the water to be the same chemically and temperature. I'd think the different chemistry may stress some less tolerable animals.

[Ninong]

I didn't know if a switching circular type of flow pattern was prefered over a "stuff blowing everywhere" type of pattern. I thought maybe it didn't matter but I'm am certainly not even close to being experienced at all. Seems to me in the wild that it would be mostly pretty turbulent with no consistent flow pattern.

In nature corals are subjected to the laminar flow patterns of the tides and turbulence of wave action near the surface. Obviously corals that live closer to the surface (e.g., Acropora spp.) experience more turbulence than corals that live 20 or 30 meters below the surface. In general, SPS require more water turbulence than most other corals because that is what they have adapted to over the ages.

The goal of the average hobbyist is simply to provide decent water flow in all areas of the aquarium, including across the surface of the sand bed. For the advanced hobbyist, especially one with a really large aquarium, the possibility exists to attempt to mimic the semidiurnal tidal patterns by using two or four Tunze Stream powerheads (or similar) controlled so that their intensity is adjusted to mimic tidal action. The powerheads on one side would be stronger than the ones on the other side and then they would reverse that pattern to match tidal patterns. In addition, you could add a couple of Sea-Swirls (or similar) at the surface to provide constant, random turbulence. This is an interesting possibility for someone with a large tank and a large hobby expense account. For the average hobbyist, the goal is to simply provide decent water flow throughout the aquarium. (P.S. -- In really large tanks of 750 gallons or more, you could set up four Tunze Streams on each end of the tank -- two on each end four inches beneath the surface and two on each end twelve inches beneath the surface. You would then have a total of eight powerheads to operate with and you would be able to mimic storms or anything you choose by varying the intensity of the various pumps.)

I was mainly asking if it really mattered. Will it affect their growth, make them healthier, etc...or is it just "flow" that matters and nobody is concerned with what type of pattern it is. Does just changing it once in a while make the difference it takes?

Adequate water flow is necessary for good health and growth. In nature, it affects the morphology of the coral. The shape of corals in nature is affected by the turbulence of the water and the amount of available light. Corals that are deeper down tend to spread out more to expose more surface area to catch the available light and corals that are in turbulent areas near the surface tend to be sturdier than the same species in less turbulent areas. In other words, a species like Monitpora capricornis will be flatter at deeper depths and staghorn corals will have thicker branches in more turbulent areas.

What all this means to you is that you should try to have random water current throughout the tank. SPS corals should be placed in areas with strong current and LPS and most soft corals lower down in areas with weaker current. The top part of your tank will have the most light and also the most water turbulence and that is the best environment for SPS. Corals that require less light and less turbulence should be placed lower down.

[Lance]

No debate. You want between 300 and 600 gph in the sump. Just like the main tank flow is important and to high is just as bad as to low. The amount of flow you use should be customized to your setup. Just because some people can sound like they are typing doesnt mean they do.

Reefkeeping 101 – Sumps! by Marc Levenson - Reefkeeping.com

[Ninong]

Lance,

I am going to quote the specific claims you made in this thread that are incorrect so that you and any others who may read this thread in the future can see where the problem lies. The "debate" is not over whether he should run 600 gph through his sump or 900 gph through his sump, the problem that I have with your comments is that some of them are ridiculous and I can't allow them to remain on the board without correcting them.

IF the flow through the sump is to great then your equipment will not work effeciantly . Around 100 to 300 gph is good.

The suggestion that "100 to 300 gph is good" through the sump for a 125-gal tank is absurd. The very fact that you would post something like that shows a lack of fundamental knowledge of the hobby. You almost sound like some of the LFS employees I have come across. They not only give ridiculous advice, they give it with conviction.

As I said in my reply, "he should be running at least 600 gph through the sump, although 700 to 800 gph would be better. The idea of 100 gph, or even 300 gph, through the sump with a 125-gal tank makes no sense at all."

If you have a constant 600 gph passing by any equipment in the sump then its not going to work very well.

This statement is incorrect. The equipment will work just fine with 600 gph through the sump. This isn't even worthy of discussion.

If your getting 600 gph through the sump alone this would be to much.

To say that 600 gph through the sump would be too much is incorrect. This is another one of your claims that isn't even worthy of discussion. If he wants to run 600 gph through the sump, that's fine. I wouldn't go much lower than that. I think 700 to 800 gph would be better than 600 gph, but 600 gph would certainly be acceptable and it most certainly wouldn't be "too much."

In summary, those three claims of yours are the ones that are factually incorrect. We are all entitled to our own opinions, but not our own facts. Some people prefer less flow than others through the sump but to suggest that 100 to 300 gph would be adequate for a 125-gal tank, to claim that 600 gph through the sump would be "too much," and to claim that the equipment will not function properly with 600 gph flow through the sump are all statements that are factually incorrect.

This thread has run its course and I am closing it.