Flow - Is it important 24/7 ?

[Krish]

We could do a poll to confirm, but I'm pretty sure that the vast majority of reefers never change their flow output in their tank's ever throughout the course of a day (like 100% full flow half of the day and then down to like 50% during the night etc). How important is it to have 100% full capacity of your flow in your aquarium all the time (24 hours a day -7 days a week)? Do you think your fish and corals may get tired of being blasted day in and day out non stop? Do you think this has a negative impact on them? Is there any benefit of doing this (ie 100% full throttle 24/7)?

Discuss.

 

[sandra6500]

I LOVE my mp10s and they are on 24/7. I figure the ocean doesn't shut off for 10 hours a day so my tank shouldn't either

 

[Krish]

I LOVE my mp10s and they are on 24/7. I figure the ocean doesn't shut off for 10 hours a day so my tank shouldn't either

It doesn't?? You sure?? Never a calm day? I've seen them on trips where we stayed on a yacht for 7 days straight where the water almost looked like glass. Days where you can throw a beach ball in the water and it basically stays in the same spot. Would you call that "the ocean being turned off" a bit seeing flow would be minimal?

 

[akunochi]

Sure the beach ball will stay somewhat stationary, but that is only surface currents. There is still plenty of flow below the surface. A lot of misconception is found because people only view the surface which is affected greatly by the wind and external conditions. Flow underneath the surface will remain fairly consistent because it is controlled moer by the lunar position (IE your tide + and -) While there will be days with less of a tide swing there is hardly ever (I almost want to say never) a 0-0 tide where the water stays slack.

 

[Krish]

I sit many days stationary on a reef when it's calm without having to kick with sea fans pretty much stationary compared to days when you basically have to hold onto the reef because you are being pulled in every direction. I don't usually go deeper than 25-30ft because my ears can't take it, but calm on top, same down below at these depths.

Merging posts


To add to that, days fishing on the rocks or off of the boat is another good example. Calm water, you can use a small sinker and toss out your line and it will sit on the bottom. A day when it's choppy or you have a lot of current, you can use heavier sinkers and still your line drags on the sea floor so it can't always be a lot of current under the water regardless of it is calm on top or not. Then there is the changing of the tide. There is a period there we call "slack tide" where for about an hour between the changing of high tide and low tide and vice versa, the water current basically sits stationary before it shifts. During this time, things are at a stand still. It is during this time you have fish like mutton snapper that will only bite during slack tide so you will usually go right before the tide changes and fish through the slack tide and about an hour after. What you don't catch then you won't. All these things taken into consideration, I'd imagine a pounding 24/7 isn't best???


Thoughts??? Do corals enjoy this time as fish like mutton snappers do as they seem to feed best when it is calm??

 

[Krish]

One last thing I'll throw out for now...Take a look at this picture below. The red arrow shows a lot of current through a channel. If you swim in this cut or on either side depending on the wind, you have a lot of current to swim against. Well this area (particularily the south side) is known to have a quite a few conch's and so one day they asked me if I'd go over. They know all they have to do is mention jumping in and I'm there . So they threw out a rope and pulled me behind the boat so I could look for them. If you see one, you'd raise your hand so the boat could know to stop, and you would let go and go down and grab them. Well, I let go and when I swam down I ended up like 30 feet away from where I was supposed to go. Came up and tried to swim towards the boat and basically kicked with all my might and I remained pretty much stationary. I could not swim against the current. They pull me on the other side marked by the blue arrow and I could stand up on the bottom and not be pushed over by the current.
So some days, reefs are pounded by alot of flow and some days they aren't. Do we mimic this in our tanks?

 

[user 2204]

Good points Krish. Being a diver myself I'd have to agree that if we as reefkeepers always blast or tanks with 100% flow, then we are not really replicating the true ocean currents.
Now if we have an alternating current or some way of allowing our tanks to be in a constant variable flow state, I would think that only then are we truly replicating the natures oceans of the world.

Personally I have scuba and snorkeled at depths of up to 82 feet in places such as California, Puget Sound (Edmonds, Alki, Mukilteo, and Keystone) and a few different areas in the Western and Eastern Carribean. All of which had different amounts of water current depending on a lot of variables. High tides, low tides, along with weather conditions contribute to the current in the oceans around the world. I've been diving at Edmonds and Alki at low tide and water was very calm. But I've also been their when the tide started to come in and the water current was thrashing us around like we were nothing.

Cheers,
Alex

Here's a few good informative links on Ocean Currents.
Ocean Currents and Climate
Ocean Currents
Ocean Planet:Ocean Currents

 

[TJL]

Great subject Krish, and for the first time I will address this in my new system. My plan is to have the lower back two PH's turn off for a night mode, where my Tangs can take refuge from the currents to sleep. During daylight hours the PH's will blast water into and behind the LR aquascape. I plan on setting up another Gyre water flow pattern in this tank but, will also be utilizing a Sea-Swirl on the return pump to a bit more random. Maybe when the Vortech pumps become more cost effective (to me) I'll setup a rotating gyre or something who knows...

Todd

 

[NC2WA]

my closed loops alternate throughout the day and then all one then all off around 4am..the goal is to get a circulation pattern for the corals which are now fewer since my tank is turning to more of a FOWLR.

 

[akunochi]

Well to be honest I do have my MP40's kick into night mode for 8 hours a day...

 

[Ugla]

On my new setup I added a Reeflow Dart on an Oceans Motions 4 way. It raised the temp in my tank to 84, so rather than get a chiller I set my controller to run it for an hour and a half and off for an hour. Now the temp stays down and everyone seems happy. My RBTA is right in the flow of an output. It gets blasted for every 15 seconds for a while, then gets a break.

 

[returnofsid]

I do believe that there are a lot of variables, in natural currents, that do allow for "slack time," when the currents are more gentle than at other times. Replicating this, in our aquariums, is possible, with controllers or higher end controllable pumps/powerheads. If we're able to do this, I don't think it's going to harm our livestock, and may possibly benefit it.

 

[mojoreef]

I think as reefers we all try a little bit to hard to recreate the what happens in the wild and tend not to look at "How does the critter use it enviroment" in order to survive/suceed/enable it.

In regards to natural flow on the reefs, yes their are slack periods, strong periods and pretty much everything inbetween. So what if we took a look at what is it that corals use this flow for?? or basically why are they so successful in these areas. I have spent many years diving on reefs and with the exception of lagoonal reefs they all seem to benefit from the same basic flow patterns. Strong currents will pull in vast up-wellings of microscopic life from much richer waters (the reef in nutrient starved) that sit deeper in the ocean just off the reefs. This flow brings in the food source and it is utlized by the corals themselves and by the fish, who then share 90% of that back to the corals. The on the out flow of tides you will see it act as a kind of flush system, where waste and various detritus is taken back out to the more deeper ocean and is then cycled in the different zones. Also with the flush out you will see an amount of fresh nutrients brough in from the slacker areas such as lagonal zones and similar. One big thing also to concider is that ammount of oxygenated water that is brought into the reef in this process also.

When we look at the whole big picture of a reef and its surrounding areas you can get a picture of what is happening, we try to recreate it but we have no chance because of the scale. So lets look at some examples.

In a wild reef, water flows in on the tides, this brings in a food source for corals/fish et al.. from the nutrient rich (and thus microscopic life forms) deeper waters just off the coasts. Atthe same time it is doing this the tide also pushes detritus/excess food and similar into the lagoonal and beach (sand bed folks??) areas.
When the tides go out it does the exact same thing, the water flow flushes the excess nutrients off the reef and pushes them back out the off shore zones where it is used and reduced in the various water level zones (birth center of various planktons, both animal and plant). Also as this is happening it pulls nutrients and larval food sources from the laggonal areas and brings them as a food source to the reef itself.

Now you mix in other stuff like airation and so on you tend to get a different picture of the actual use of water flow on and across the reef. Is it to make the corals feel sexy with all that water flowing around them?? or is it simply to serve dinner and then to clean up after it?? For me (and this in just imho) I tried to design my flow to come close to the latter. So not that it gets strong and then slack, but that it gets some kind of alturnating flow that allows the various areas with in my system to see flow go past it in a couple of directions. This will them allow detritus/waste/excess food to be made both available to the corals and then to allow what is not to be used to be directed towards a place where I can treat (overflow and then sump) the water and then return it to the system. So can you put a GPH to this?? nope you just have to loof how the flow covers and thus effects the corals in the tank.

anyway not sure if I muddied that up more or put some clarity to it.

Mojo

 

[Skimmy]

for aquariums,
i think all on 24/7 is better...
lets face it, our aquariums are not the ocean, and as mojo mentioned,
we might at times get a little too hung up on trying to mimic the exact reef conditions in a closed system.

i think the shape of the aquarium plays a big roll in limiting the ability of flow to mimic the ocean,
and also, if you have a fish only or reef system will play another part in how important 24/7 flow is...
i.e in a fish only system or fish dominated system i would consider turning the flow down at night for the sake
of resting fish, but a coral dominated system i would want full flow 24/7 for the purpose of allowing the corals to respirate
fully at night as much as in the day. i also wouldnt want to allow detritus any time when it could collect more than another.
I do think there is some merrit to the idea of flow in the ocean being less at night due to the lack of solar driven wind energy,
but that as mentioned the lunar cycle will power the majority of that flow 24/7. but shallow water on the fore reef
(which our reef tanks mimic the closest) would be more effected by the lack of solar wind activity than deeper reefs at night as well.

 

[Krish]

Good points. The part about trying too hard to mimic nature I'm not sure I can 100% agree with. We do try to mimic nature. Think of the flow again in our tanks and think about it in the wild. Flow pattern in the wild changes throughout the course of the day with low tide and high tide. Usually there is a shift with the tides direction and the wind plays a major role here as well. So when a newbie asks how should I set up my flow what is suggested? Random flow. Not flow from just one direction. This is where sea swirls and oceans motions etc come in to play. Designed to create random flow like where? The ocean? We are trying to mimic nature here so we look at the changing tide and flow patterns and we try and mimic that. If not, we'd say just straight directional flow will do. The slack tide I spoke about which lasts only about an hour where fish like mutton fish feed best reminds me of the feeding settings alot of powerheads and even power filters have. An option to shut off/slow down flow for a few mins to feed. Designed almost to work like nature huh? So we are trying to mimic nature as best we can. Sometimes we do it without realizing how much we are doing it. Light cycles mimic nature as no one I know of runs a 24 hour photoperiod on thier DT. Also, alot of people try to mimic dusk to dawn effect to mimic sunrise and sunset. Water parameters mimic nature as we shoot for parameters found in the water our corals mostly come from. Natural food brought in by the tide is not possible in our tanks so we mimic nature and "feed" our tanks. Waste removed by the tide we mimic through the use of mechanical filtration etc. Aeration which is supplied by the water currents in nature is supplied by pumps and skimmers so I think if we want to have any success in this hobby we need to use nature as our guide and try mimic it as much as possible especially seeing we are in a closed system. Too much against us to start off with. If we don't try to mimic nature then what is our guide? If our tanks don't naturally provide something we accommodate it through the use of different equipment, trace elements dosed, lighting etc.

Just a few more thoughts. Should not be posting and driving

Sent from my iPhone using Tapatalk

 

[mojoreef]

Sure Krish we have to mimic nature for basic requiremtns of the critters we keep, you could even go farther and say we use water and that is found in nature. arty: I am not trying to throw a wet blanket over the concept, just trying to show that its impossible to mimic nature, what we should be doing is drilling down and try to recreate what nature is doing by the actions that happen in it.

So let look at say tidal flow, in nature billions of gallons flow onto the reef and take away vast ammount of detritus/waste and so on. This would be equal to doing hundreds of water changes a day, not realistic. But if we drill down and look at it we can say that natures natural path is to remove as much detritus and so on as much possible, so concentrate on that.

Tides/cross tides, wind, wave action in nature is used to again remove detritus/waste, make food available, povide oxygen and so on. As reeers if we tried to recreate this it could get pretty messy. So we cant recreate waves breaking over the reef providing airation? but we can use a skimmer to inject air, maybe keep the surface tension down? Is that like nature? no but it fufills the need.

So Its not like we are on totally different pages here, I am just saying recreate the effect not the method?? When we go after the actual process we can only fail as we cant meet any requirements from a scale perspective.


Mojo

 

[Krish]

Sure Krish we have to mimic nature for basic requiremtns of the critters we keep, you could even go farther and say we use water and that is found in nature. arty: I am not trying to throw a wet blanket over the concept, just trying to show that its impossible to mimic nature, what we should be doing is drilling down and try to recreate what nature is doing by the actions that happen in it.

So let look at say tidal flow, in nature billions of gallons flow onto the reef and take away vast ammount of detritus/waste and so on. This would be equal to doing hundreds of water changes a day, not realistic. But if we drill down and look at it we can say that natures natural path is to remove as much detritus and so on as much possible, so concentrate on that.

Tides/cross tides, wind, wave action in nature is used to again remove detritus/waste, make food available, povide oxygen and so on. As reeers if we tried to recreate this it could get pretty messy. So we cant recreate waves breaking over the reef providing airation? but we can use a skimmer to inject air, maybe keep the surface tension down? Is that like nature? no but it fufills the need.

So Its not like we are on totally different pages here, I am just saying recreate the effect not the method?? When we go after the actual process we can only fail as we cant meet any requirements from a scale perspective.


Mojo

Makes sense...So you say blast away on the flow 24/7 (I mean that's what I do). There would be no real benefit in cutting down flow for a few hours a day as the only thing that may benefit from it is maybe giving the fish a little break with them not having to swim against the current in our tanks 24/7 (especially at night when resting), but other than that, no real benefit?

 

[mojoreef]

Brother you can do anything you want!! Anyone can. I am just saying I think we spend a little but to much time trying to recreate instead of trying to care of the end result of the thing? If you want to kill the pumps for feeding, or for sleeping by all means do it, your reef tank and the hobby needs to please you, no one else. Is any of it a requirement, some things are, random alturnating flow that keeps the detritus in the water column absolutely is, recreating a tide?? dont think so. Same for fish sleeping?? I am sure they can find a place in the rocks (whch they do) that is calm enough to sleep in and so on and so on.


Oh and fish like to swim hehe it helps them breathe

Mike

 

[Krish]

Well it's not a matter of doing what you want because it is your tank and you have to do what makes you happy, but rather the main point is being missed. I know this thread went off track a bit from the original post and question so here it is a gain. Special attention taken to the questions underlined and in bold...

We could do a poll to confirm, but I'm pretty sure that the vast majority of reefers never change their flow output in their tank's ever throughout the course of a day (like 100% full flow half of the day and then down to like 50% during the night etc). How important is it to have 100% full capacity of your flow in your aquarium all the time (24 hours a day -7 days a week)? Do you think your fish and corals may get tired of being blasted day in and day out non stop? Do you think this has a negative impact on them? Is there any benefit of doing this (ie 100% full throttle 24/7)?Discuss.

So we try to replicate nature in most cases with our tanks. The question is, if we do this with flow, is there any negative affects in our aquariums with blasting the tank 24/7 or changing it up a bit and have periods of less flow or not much flow at all? Do the corals benefit from periods of slow flow? Like do they spawn or whatever during these times in the wild (as an example). Are they affected in anyway from being blasted 24/7 negatively? These are the questions and not so much doing what makes you happy. Wondering if nature is telling us something with the way water movement in nature changes up a bit or is it just a flaw in the "nature of things" and during these times of "slack tide" or hardly any water movement in the ocean that corals and fish kick into a "survival type" mode waiting for the flow to pick back up which is required of them 24/7. That's the point of the thread..Any negatives or positives to 24/7 blasting of flow or changing up like nature. Nevertheless, during your posts you answered the questions so the thread served it's purpose.

 

[mojoreef]

Ok let me see if I can make it clearer as it pertains to your original question.

So as it pertains to acros and hard corals = If you take two identical frags off the same mother colony and then put one in very high flow and then the other in a slack flow you will find that the coral in flow will grow slower and thicker, the slacker flow coral will grow thinner and faster.

If you take a power head and point flow down onto a plateing coral such as a monti, the coral will grow downwards firstly and then thick up and try to clever up into the flow. Put the flow from under and it will just thicken up and continue to grow.

Fish will find slack areas in the tank to sleep rest and so on, they will come into the flow to feed and to oxygen up.

So as per corals they will adapt, they have for millions of years, its why they are still around. A few years ago a study showed that half the corals (mostly what we call SPS) were actually them same corals, even though marine biologist had named them as a unique species. What they found was that the corals had adapted and mutated to master the current enviroment they happened to land on. Neat stuff really but perhaps a different subject for a different day. So when one looks at all of these various scenerios, what I am saying is look at what the enviroment does for the health of the coral, not so umuch the mean by which it does it?? make sence? Beyond that every hobbist should take from the hobby what interests them and/or what they like about it, once you put that into the equation then it all boils down to "As long as you are providing what is required for the coral to live, do what makes you happy"


Mike