How important is random flow for SPS

hoyta · #1 09/26/2007, 10:33 AM

Hello all!
I think the SPS bug has bit me!
I have a 65 gallon, with 2 Seio 820s in it as of now. I really can't afford Tunzes, but would like to keep SPS. What are my options??
Oh yeah, my return is a pan world 40x

Marko9 · #2 09/26/2007, 10:38 AM

The key to SPS is trying to mymic the real thing. You can keep them, but they will not thrive. Start of with some montis or yongei.

jay24k · #3 09/26/2007, 11:02 AM

You don't need random flow at all. I have 2 Vortechs and there is no random flow as of yet. I've had my tank for over 2 years and the color and growth are out of the roof.

crazedreefer · #4 09/26/2007, 11:27 AM

Quote:

Originally posted by jay24k
You don't need random flow at all. I have 2 Vortechs and there is no random flow as of yet. I've had my tank for over 2 years and the color and growth are out of the roof.

I agree...You just need alot of flow and having alot of flow cause choatic flow which they like...

If you can not afford tunzes, do not worry about it get more seios or the new korilias...

TomRep · #5 09/26/2007, 11:35 AM

Agreed, random flow is not a must. There was an article on Reef Keepers about this. I have a semi-variable flow in my 120. 2x Maxi modded 1200, 1x Maxi modded 900 with two closed loop outlets shooting straight out of the back. The two closed loop outlets are on a squid, so it gives me a semi-random flow when the CL outlets hit the MJ mods. I still want to add atleast one more Maxijet. Oh yea, my return pump is a Mag 5.
tom

IMPERATORFAN · #6 09/26/2007, 12:40 PM

Random flow is not a bare necessity, but it I feel it does go a long way in contributing towards good even growth. Some sps (stags in particular) will tend to grow down stream and not look natural.

MCsaxmaster · #7 09/26/2007, 01:44 PM

Polyp size is completely and utterly meaningless in waterflow requirements. Some "sps" corals live in very calm water in nature and thrive. Others live in ridiculously strong surge zones and thrive. The size of the polyps is...meaningless.

If you have lower waterflow you need to pick corals that live in lower waterflow. A table-top Acropora would be a terrible choice. A branching Montipora or a Pavona would be an excellent choice.

Random flow/oscillating flow increases the rate of exchange of materials (nutrients, oxygen, waste, etc.) between the coral and the water column relative to the same rate of water flow coming from one direction. If the corals are able to exchange oxygen, waste, nutrients, etc. with the water fast enough with unidirectional flow they'll be fine. If they are not able to do this, then random/oscialltory flow will help. Typically this becomes more problematic with larger colonies (the inner branches don't get the same water flow as the outer branches). Just increasing the rate of flow (unidirectional or otherwise) often can take care of the problem.

cj

manderx · #8 09/26/2007, 01:47 PM

i've always felt that it was easier for a polyp to catch food with back&forth flow than unidirectional flow.

MCsaxmaster · #9 09/26/2007, 01:57 PM

You'd be correct

At a given flow speed, rates of mass transfer for corals has been measured at up to 3x as fast when flow is oscillatory as compared to unidirectional. Mass transfer is the rate of exchange of material between coral and water column--in this case, the capture of zooplankton from the water.

cj

surfnvb7 · #10 09/26/2007, 05:24 PM

IME......if you have say a MJ not on any sort of wave timer, giving a direct flow right onto a coral.....the coral will tend to grow at an angle in the direction the flow is going towards, just like a tree swaying in a breeze.

looks kinda odd and unnatural IMO....

Randy1 · #11 09/26/2007, 05:30 PM

Just be sure to have water flow in as many directions as possible, forget the wave makers.

eddtango · #12 09/26/2007, 06:28 PM

Tunze Streams with controllers will be good for an sps tank.

MCsaxmaster · #13 09/26/2007, 06:33 PM

...or a reef tank with animals that enjoy strong waterflow. The designation "sps" has nothing to do with waterflow needs. Some need a lot, others don't. Same for "lps" corals and soft corals and zoanthids, etc.

cj

matt the fiddler · #14 09/26/2007, 06:53 PM

"I have 2 Vortechs and there is no random flow as of yet"

having that wide of a flow does create random flow. it is nto as random as a tunze.. but in no way is it 100% stationary...

MJAnderson · #15 09/26/2007, 08:00 PM

Quote:

Originally posted by MCsaxmaster
You'd be correct At a given flow speed, rates of mass transfer for corals has been measured at up to 3x as fast when flow is oscillatory as compared to unidirectional. Mass transfer is the rate of exchange of material between coral and water column--in this case, the capture of zooplankton from the water.

cj

Can you cite that?

jay24k · #16 09/26/2007, 09:30 PM

While I agree, 2 could offer some type of random flow but in a 6 foot wide tank, the two vortechs don't really add that much random from what I've seen. Will corals grow better with a random based flow? I don't know if it has ever been proved but it is always possible.

mxett · #17 09/26/2007, 10:47 PM

I have a 4 foot long tank and have a tunze 6000 running full blast down one end, and 2 modded 6045's down the other end (plus an eheim 1252 return from my sump). I direct the pumps so they create whirlpool flow, ie they are all pushing the flow say clockwise in the one direction around the tank. Because they are all pushing together, they achieve tremendous water speed. When this fast moving water collides with rocks and corals it becomes very chaotic. Im my tank this is easy because I have my rocks and corals in the middle, not up against a side, so i can see it from each side.

THEN every 12 hours I put my hand in the tank and redirect the flow so it goes counter clockwise. Then the corals experience rapid flow from the other direction. To my logic it would be similar to what many shallow corals would experience when in areas effected by tidal flows.

So far I have had excellent success with this method.

matt the fiddler · #18 09/26/2007, 11:35 PM

the tunze's have the tidal feature for that. but in nature it is every 6 hours

I run my tunzes on growing flow, but so it grow for 3 mins or so, then completly shuts off [no pump plugged into channel 1] that varies not just the flow, but also the sediment traps.

random flow is great depending on the coral, each coral grows differently becasue each has it's area to thrive.. there are corals that live in rip tide channels that get very steady flow, etc. but no tas steady as a powerhead in a reef tank...

IF you want large mature colonies, start the flow when they are small, or they will have morph changes when you do crank up the flow later.. frags don't really IMHO, need the random and strong flow that a mature colony has. if you think of it, branches block and asorb the energy... having it be hit from every possible side ensures that all parts of the corals will thrive. I wish my tank was secure enough for a wave box

it is falling apart at the seams as it is!

MCsaxmaster · #19 09/27/2007, 12:44 AM

Quote:

Originally posted by MJAnderson
Can you cite that?

Reidenbach, MA, JR Koseff, SG Monismuth, JV Steinbuck, and A Genin. 2006. The effects of waves and morphology on mass transfer within branched reef corals. Limnology and Oceanography. 51: 1134 - 1141.

cj

HBtank · #20 09/27/2007, 01:08 AM

How about that gyre "article" MJ?

mxett · #21 09/27/2007, 01:12 AM

Quote:

Originally posted by matt the fiddler
the tunze's have the tidal feature for that. but in nature it is every 6 hours

I run my tunzes on growing flow, but so it grow for 3 mins or so, then completly shuts off [no pump plugged into channel 1] that varies not just the flow, but also the sediment traps.

random flow is great depending on the coral, each coral grows differently becasue each has it's area to thrive.. there are corals that live in rip tide channels that get very steady flow, etc. but no tas steady as a powerhead in a reef tank...

IF you want large mature colonies, start the flow when they are small, or they will have morph changes when you do crank up the flow later.. frags don't really IMHO, need the random and strong flow that a mature colony has. if you think of it, branches block and asorb the energy... having it be hit from every possible side ensures that all parts of the corals will thrive. I wish my tank was secure enough for a wave box it is falling apart at the seams as it is!

Matt, I realize 12 hours is a bit longer than a tidal cycle, but who wants to get up in the early hours of the morning to redirect flow

. I'm sure the corals don't have their clocks out wondering "why hasn't this tidal flow changed direction yet"?. I think they enjoy the great flow and are happy to wait a bit longer until it all changes again.

MCsaxmaster · #22 09/27/2007, 01:19 AM

No, I'm pretty sure they do in fact have wrist watches

MJAnderson · #23 09/27/2007, 08:59 AM

Quote:

Originally posted by HBtank
How about that gyre "article" MJ?

Do you even read the stuff you cite?

The amount of turbulence they are talking about in both of those articles is LESS than the turbulence created using 4 400gph powerheads on a timer. So if varying 2 800gph flows can top the highest reading in the ocean by 15%, you feel that blasting it with 2 3,400 flows can only be better?

And the increases are hardly earth shattering:

"Assuming an average turbulence intensity of around 25%, then ignoring the effects of nonlocal turbulence altogether would result in uncertainties in mass transfer coefficients of at most ±10% for the lobate coral form and ±5% for the branched coral forms"

Sorry, no matter how sweet your corals look, you still haven't made a convincing arguement for why you need massive amounts of random flow.

kimoyo · #24 09/27/2007, 10:15 AM

Quote:

Originally posted by MCsaxmaster
You'd be correct At a given flow speed, rates of mass transfer for corals has been measured at up to 3x as fast when flow is oscillatory as compared to unidirectional. Mass transfer is the rate of exchange of material between coral and water column--in this case, the capture of zooplankton from the water.

cj

Wouldn't random and oscillatory flow be different?

If its oscillatory what type of period? Are we talking seconds, minutes, hours?

Thanks

MJAnderson · #25 09/27/2007, 10:57 AM

Quote:

Originally posted by MCsaxmaster
Reidenbach, MA, JR Koseff, SG Monismuth, JV Steinbuck, and A Genin. 2006. The effects of waves and morphology on mass transfer within branched reef corals. Limnology and Oceanography. 51: 1134 - 1141.

cj

I could only find the summary, but that states a maxiumum 10% increase, 5% for branched corals. Where do you see 300%?