What's your turnover rate in your sps tank?

[JPMagyar]

To the OP and anyone interested in the original question of "how much flow" I will offer 2 simple facts:

1) This is my tank

2) I use a LOT less flow than is "proper".




If you have ever been diving you know that you are not swept off the reef by thousands of gallons per hour of flow across the reef. The types of flow and direction are so variable on most reefs as to be impossible to quantify precisely. Research has shown that variability is more important than quantity. Laminar flow, no matter the amount is not as beneficial as variable flow. I ran 2 6205 Tunzes on a 240 gallon tank each one running only one at a time, and i felt that was too much so I switched to a 6105 and a 6095 (nano pump) operating on alternate timing while my main return barely does 300 gph on a 700 gallon system. I have found that when some of my corals grow too large and restrict flow then the tank suffers. It's not the amount of flow that counts. It's the fact that flow reaches every inch of your corals and that the flow is variable. Dead zones kill corals and that's why we think flow needs to be so high.


You can have a great tank with low flow, and you can have a great tank with high flow.



Joe :beer:

 

[TimothyJ]

I have a 30 gallon nano (24 x 24 x 12).

I run two MP10's at around 65% on reef crest (therefore percentages vary quite a bit).

1,500 GPH x 65% = 975
975 x 2 = 1,950 GPH
1,950 / 30 = 65 turnover

I would bet my number is closer to 40 just because the pumps vary their rate so much.

 

[coralreefdoc]

Joe. Let me start by saying I greatly respect most of your work in the hobby and what you have accomplished with that 240Cube

Now ...

Have you actually been diving, more than a handful of times, within the confines of a "true" tropical reef crest/flat system ? It goes without saying that I have, and I can assure you there were multiple times where you're swept along so briskly, by the prevailing current, that in order to stay still you in fact do have to hold on to the reef structure (spot where there is no coral growth for the noobs/oblivious) ...

"Or be swept off the reef by the 'MILLIONS' of gallons per hour of flow across the reef."

Does this happen continually throughout the day/week ? A resounding no, but it is common, especially in higher flow locals/regions or areas along the edges of dominant oceanic gyres, such as the Gulfstream Current associated with Floridas Coral Reef System ... In fact, the prevailing current even switches direction, thus producing a phenomenon similar in nature to slack tide, throughout the course of the day/week. As you touched upon with your explanation of variability in flow patterns.

Moving on, you're theory of quantity/variability of flow is somewhat contradictory ...

The sheer quantity of flow that moves up, over, around, and thru a coral if FAR more important than the type of flow it originated as I.e. variable, laminar, etc. Take, for example, an Acropora subulata with its bushy structure, and tightly constricted base/core ... The quantity of flow thru that specimen, even a 100% laminar flow, will indubitably prove to be more advantageous to its health than say a variable flow which does not produce enough "quantity/volume" to reach the innner branches of the Acroporas core structure !

What is truly important, especially in the realm of small polyp stonys, is in fact the volume (quantity) of water mass moving thru the coral, moreso than any other determining factor in regards to flow ... The sheer volume of water moved thru the reef on a daily basis is difficult to quantify/borderline incomprehensible !

In conclusion, while it is extremely important to ensure variability in flow patterns/rates, the true determining factor of success with SPS, in terms of the flow variable, is the quantity/volume of water moved around/over/thru the corals structure and slightly lesser more the velocity of that water.

 

[ashish]

To the OP and anyone interested in the original question of "how much flow" I will offer 2 simple facts:

1) This is my tank

2) I use a LOT less flow than is "proper".




If you have ever been diving you know that you are not swept off the reef by thousands of gallons per hour of flow across the reef. The types of flow and direction are so variable on most reefs as to be impossible to quantify precisely. Research has shown that variability is more important than quantity. Laminar flow, no matter the amount is not as beneficial as variable flow. I ran 2 6205 Tunzes on a 240 gallon tank each one running only one at a time, and i felt that was too much so I switched to a 6105 and a 6095 (nano pump) operating on alternate timing while my main return barely does 300 gph on a 700 gallon system. I have found that when some of my corals grow too large and restrict flow then the tank suffers. It's not the amount of flow that counts. It's the fact that flow reaches every inch of your corals and that the flow is variable. Dead zones kill corals and that's why we think flow needs to be so high.


You can have a great tank with low flow, and you can have a great tank with high flow.



Joe :beer:

Smart words from a smart reefer:thumbsup: The problem is most peoples answer to flow with SPS is they need "High, strong, 30+turnover". It should be "random, turbulent, gentle,". There is no way you'll achieve random and turbulent flow without having strong water flow.

Turnover per hour should be measured in exactly how much time each pump is on per hour taking in head pressure and length of time pumps are on. If your running a 3200 gph powerhead on "5 second's on/off", your getting 1600 gph from that pump.
I have 46 times turnover in my 120 gallon if everything was on constant for 1 hour. After determining my 950 gph return pump (after head pressure) is only 650gph, and the length the pumps are on - I have 29.5 x turnover in my tank per hour

 

[Denadai]

1x or 2x, for me is enough ( between sump and display )

 

[Dexters Reef]

In my 75 drilled sps tank, I use two MP40's, at about 85% which peaks to 5440 when they are both hitting thier max settings. This plus my return yield approx 75x turnover. (Not counting the return pump its about 72x turnover)

This is constantly varying throughout the day, due to the reefcrest programming cycle, but my corals are all looking happy and are growing well.

 

[REEF SMAC]

350 g display

(4)MP60s at 100%
(1) Tunze 6305 at 100%

This works out to over 100Xs just with powerheads

Return pump is Hammerhead split between DT via OceanMotion and 25g Carlson surge that is 8' up.

I have no idea how to calculate how much flow a 25g dump, from 8' up, 1.5" pipe, in less than 30 seconds. It is a lot.
More than any powerhead I've ever had that is for sure.

My flow DT through my sump is a least 10Xs an hour.

My Acros seem to suffer through all this flow just fine.

 

[JPMagyar]

Joe. Let me start by saying I greatly respect most of your work in the hobby and what you have accomplished with that 240Cube

Now ...

Thank-you!


Now having said that, I can't believe that I, the man who loves internet discussions, missed an opportunity to debate

Have you actually been diving, more than a handful of times, within the confines of a "true" tropical reef crest/flat system ?

In very round terms I have about 500 hours of dive time.

In conclusion, while it is extremely important to ensure variability in flow patterns/rates, the true determining factor of success with SPS, in terms of the flow variable, is the quantity/volume of water moved around/over/thru the corals structure and slightly lesser more the velocity of that water.

Ahh young paduan (did I spell that right?) I take my tank as ipso facto proof that you are incorrect in this last statement. I do not have "high flow", and my SPS are growing well therefore "high flow" can NOT be the determining factor. Do many corals live in tidal areas where they receive enormous crashing waves and/or tremendous water movement? Absolutely yes, but there are just as many reefs that are chock full of acroporas that thrive at a depth of 30 feet or so with only gentle movement and an occasional passing storm. I do not disagree that many specific acroporas can benefit from high flow, but I simply say that high flow is not an absolute necessity, and I will look for the paper on laminar flow, but as I recall pure laminar flow can cause a coral to starve therefore my second premise that variation in flow is more important than quantity of flow. If a coral can starve in laminar flow, but thrive in low flow then I would say variation is more important than strength,

BUT

I'm not a scientist and these are the musings of a mere mortal hobbyist so if you, gentle reader, happen to find my comments persuasive I only hope you will do your own research to find an answer suitable to your own condition.


Thanks CRD for the great thoughts! Maybe you're right and I'm just underestimating my Tunze output.

 

[vair]

Flow through and turn over rate? 300G DT side weir over flow, SPS LPS and fish.

My plan was to match my flow rate through the sump to that of my skimmer, 700gph Deltec ap1003.
Additional turnover in the tank would be around 7000gph pushing through a OM 4 way.

Conflicting opinions, I was told flowing that little through the sump to match the skimmer would not work and is a waste?? He was of the opinion the heaters would not even keep up to heating the main display, I'd have hot water in the sump and not hot enough in the display.
I was a little taken back by this statement, but he was speaking like it was fact? So I said I'll research more.

Thoughts?

AND Joe your tank looks amazing!!

 

[Allmost]

last time I went diving in the Caribbean I got hit against a rock due to currents ...

the water movement in oceans is alot more massive, but doesnt last all day and night, so alot more mass of water moving and alot more random

 

[djp2313]

About 40x in a 120

Looking to add more but in small amounts.