just a thought about water flow at night

[willieboy240]

so i'm thinking?:( at night the water flow is suppose to be calmer. so on a big tank wouldnt it be better to turn off the closed loop system and just run the sump return pump and one to two power heads. which will turn the tank over maybe 5 times instead of 10 times during day time hours? this would save on electricity and give the corals a rest. what did you think?:confused:

[dragon_slayer]

i dont recall the ocean turning off at night. the only difference in currents at night are surface and thermal which i dont see haveing much effect on a reef. tide's have the biggest effect of currents of the reef, but they come and go with the moon, not the sun.

YMMV
kc

[Bayliner]

I accidentally did this for a couple of months. I had 3 power heads wired into my lighting timer by mistake. Every thing in the tank looked so well I contemplated on leaving it that way when I found out...
I would be very interested to hear what others think of this as well.

Cam

[willieboy240]

i wouldnt turn everything off. just slow everything down. so everything would have a rest in the tank. bad idea?

[Bayliner]

I don't think it's a bad idea.
Anyone know much about wave makers?
Don't some of them have a day and night setting... just curious.

Cam

[kotoma]

Remember how fishermen sail? Winds change direction and intensity not by season but also by day and night. Deep ocean will not be affected, but shallow area will. It's nice if you could reduce water current at night. I reduce 25% water current from 10:00pm and 6:00am.

[Loudz34]

Humm, I might give it a shot sometime with the tank, and yes wave makers (the red sea) has a night feature that runs the powerheads at a lower setting and also a feed function so the tank is calm during night and feeding time....

[mojodeli]

The tunze multi controller has an automatic night time mode if one is employing the photocell. It turns the streams down to 30%.

I'm sure they did enough research to warrant the diminished night time flow.

[eljefe3]

I turn off my foam fractionators at night making things a little more quiet and saving the electircity of having the pump running.

[willieboy240]

so it sounds like i'm not too off then. cool. thanks people.

[dragon_slayer]

Originally posted by mojodeli

I'm sure they did enough research to warrant the diminished night time flow.


i Honestly think its just a 'bell and whistel' to sell it. as i said earlier in a post, the ocean doesnt turn off at night, so nore should your tank.


kc

[mojodeli]

Originally posted by dragon_slayer
i Honestly think its just a 'bell and whistel' to sell it. as i said earlier in a post, the ocean doesnt turn off at night, so nore should your tank.


kc

True the ocean does not shut off but that doesn't mean the fish don't find a calmer place to rest. You've got to admit that in our glass boxes such options are limited.

[dragon_slayer]

i have enough rockwork that there are plenty of calmer spots for the fish. my firefish have made a cave under the rocks that they stay in and the clowns either live in their anemone or a brain coral at night.

kc

[willieboy240]

some corals dont have a choice to move tho.

[dragon_slayer]

and they do in their natural enviornment?


kc

[Slicktrax]

The ocean may not shut off at night, but in my visits to the beach, it is generally calmer at night than during the day.

[dragon_slayer]

not in the gulf of Mexico, or the Atlantic cost along Fl and Ga IME. granted i probably havent been to the beach more then a few thousand times at night.

the ocean's here change with the tide, and the tide comes and goes with the moon, not the sun.

kc

[dgasmd]

Well, I am making osrt of a compromise for other reasons. I will ahve 2 of the sequence 5800 gph pumps as close loops and one AM3000 close loop in my 360 gal tank. The returns are 2 on eductors with a iwaki 100 driving them. I will turn off the AM3000 at night which supplies flow mostly to the bottom part of the tank (no sand bed). The reason is that I will already have more than plenty of flow left regardless of it, but it will provide a more calm larger area for the invertebrates and fish to settle in at night and have a place to roam around without getting blown off.

[mojodeli]

Do you think weather doesn't affect the ocean? Do you think the sun does not affect weather?

This ocean is slightly calmer at night simply because the convolution between warm and cool air masses is diminished. This is science not anectdotal evidence as your visits to the atlantic and gulf of mexico suggest.


Originally posted by dragon_slayer
not in the gulf of Mexico, or the Atlantic cost along Fl and Ga IME. granted i probably havent been to the beach more then a few thousand times at night.

the ocean's here change with the tide, and the tide comes and goes with the moon, not the sun.

kc

[dragon_slayer]

Originally posted by mojodeli
Do you think weather doesn't affect the ocean? Do you think the sun does not affect weather?

This ocean is slightly calmer at night simply because the convolution between warm and cool air masses is diminished. This is science not anectdotal evidence as your visits to the atlantic and gulf of mexico suggest.


the ocean plays a bigger part on weather then weather on the ocean. at night when the sun isn't directly on that part of the ocean, currents are different only on the surface where thermal currents are at. also wind tends to pick up at night from the cooling air which is falling downward this causes currents.

as far as the sun having an effect, its more so based on the earth in relation to the sun, the sun is closer to the earth during the winter in the northern hemisphere...........but amazingly enough its colder. that my boy is science.

now throw the moon in and you get some amazing things going on in the ocean. they come about at roughly 12 hr intervals during a 28 day rotation. they are called tides and have the biggest effect of currents in the oceans, weather aren't a drop in the bucket compared to the moon.

maybe you need to spend a few days/nights out on the big pond in a small boat and see for yourself.


kc

[ddoering]

Why do people try to compare a box of saltwater to the ocean.

Yes, the ocean doesn't turn off at night, but what does this have to do with maintaining an aquarium?

The ocean does not require extreme measures to maintain water quality/salinity/temperature like an aquarium.

The ocean does not have the limited diversity as far as a food chain as an aquarium does.

The ocean contains creatures that are constantly breeding and constanty dieing.

The ocean contains a multitude of environments that all interact to a semi-stable whole.

An aquarium is an attempt to maintain a specific subset of animals/plants in a limiting environment.

I don't really care if the ocean is calmer at night or during the day, or if the difference is negligible when compared to tides.

My concern would be if in keeping animals in an aquarium, does a quieter period (night or day doesn't matter) make for healthier animals, cause the animals stress, or doesn't make a difference to the animals?

If the answer is healthier animals, or no difference, then why not have a quiet period at night?

It would help reduce costs of maintaining an aquarium, or allow you to spend that same money on larger tanks, better pumps, lighting, etc.

It also may be a concern to people for noise reasons to want to have a quiet period at night, and if it doesn't hurt the tank, and makes the owner happier, great.

I can't say what makes more of a difference in water flow in reef areas, and would be interesting if anybody found a study on tidal affects vs. ocean currents. Also, I'd assume there is a lot of difference based on the different types of reefs, barrier, shallow, deep reefs etc on what is more an affect of the current in that environment)

Ocean currents are also constant, and driven by temperature differences between warm tropical waters and colder ocean waters (think of a convection current) so are driven by the Sun, but not on a day/night cycle, more of a tropical vs polar thing, and also the rotation of the earth.

As far as "science" is concerned... it being colder in the northern hemisphere during the winter even though the earth is closer to the sun proves nothing. The tilt of the earth and the number of daylight hours is what drives winter/summer seasonal changes. It will also affect the winds and ocean currents (look at shifts in the jet stream) which then brings cold air down from the arctic over a lot of North America.

Another food for thought, how long have the creatures in the reef areas been living in basically static conditions? The moon is receding from the earth every year, so tidal affects today are a lot less than they were thousands of years ago. Also, as the moon gets further away, the affect on tides is not going to be linear since gravity functions by some inverse square law or something (been a while since physics class).

What is the difference in water levels from tides anyway? Does it compare to the tidal surge brought on by a decent sized storm/hurricane?

Tidal affects, the sun, and weather are all so interrelated that I don't think you can try to subdivide them down to one having a greater affect than the other.

So again, back to the question, do people in their experience see a benefit or a detriment to the health of their aquariums by having a calmer period of water flow?

Thanks,
Doug

[o2manyfish]

A Few Answers:

1) DGASMD - Turning off the Ampmaster at night for your closed loop is a bad idea -- I am a big fan of the Dolphin pumps. But it is a pump that doesn't consistently turn back on - Because of the Low RPM High Efficiency motor, and the quite tight seal, about 1 out of 5 restarts the pump will not be able to spin itself up. If it doesn't spin up it will burn the motor after a period of time. You have to physically get your finger in there to hand spin the shaft.

2) The reefs closer to the equatorial line have less impact from tides. While the tidal flux in Hawaii may be as much as 20 feet a day, closer to the equatorial line it is Zero.

3) A beach is calmer at night, the ocean is calmer at night. But these are surface issues. For those with diving experience know that no matter how rough the water is on the surface, once your under the surface there is minimal effect from wave action. So the currents going across the reef are quite consistant and don't vary pending the surface action.

One of the interesting things I came across while experimenting with flow issues was using a fountain in one of my outdoor ponds. By stands a pump on the bottom aiming out the top of the tank, the water falling back down on itself creates a really unique constantly varying wave action. The wave pressure in the tank changes every couple of minutes - Some times the tank is flat and then the wave pressure builds up till it slops over the sides.

But what is most unique about this is that when you looks at the polyps on the corals the polyps flip back and forth every couple of seconds. I have a friend who I showed the fountain to, he tried it as well. We are getting much better polyp extension and growth. In the wild the current flows back and forth against the corals in intervals of several seconds. However, all the wavemakers out there don't come close to shifting the flow back and forth every couple of seconds in our tanks.

I leave the fountains on 24/7. The corals are loving it. As for the fish, they always can find a place in the rock work or within the corals for a comfortable sleeping spot.

Dave B

[rspar]

On kinda of an off-shoot for a closed loop if you had access to little giant brand pumps which would you use for a closed loop on a 60g cube. Gph wise something in the 1000 area but which one is the quietest of the Little Giant's and do they compare to the quietest pumps of other brands?

[ddoering]

Hi Dave B,

thanks for your experience, although I don't think I can mimic that type of setup inside because of salt spray etc.

what kind of setup do you use for indoor display tanks to vary the waterflow? rotators? or scwds, or alternating surge devices that aren't the same size so they are constantly changing the water flow?

Cheers,
Doug

[o2manyfish]

Doug,

I was using the SCWD's, I had 2 each one running off a RIO 1700. I recently removed the SCWD's and set the RIO's up so they are aimed straight up in the tank and the water is deflected off the top of the tank bracing (I have an Acrylic Tank). In addition the returns for the tank are 1.5" spraybars that are run off a Hayward 1.5" motorized ball valve that switches every 15 min during the day and every 45 min at night - The reason for the difference at night is because of the noise the valve makes switching.

I use 1/2 the output from a Dolpin 3K for the motorized valve, and the returns are on each top corner of the tank.

Dave B

[gbtower]

Originally posted by o2manyfish
I recently removed the SCWD's and set the RIO's up so they are aimed straight up in the tank and the water is deflected off the top of the tank bracing (I have an Acrylic Tank). In addition the returns for the tank are 1.5" spraybars that are run off a Hayward 1.5" motorized ball valve

Very interesting idea. Do you lose the effect if the spray doesn't shoot above the water surface? Perhaps this can work with smaller pumps and smaller tanks. I wonder why it wouldn't work in other orientations like straight down or straight against a tank wall. Your motorized valve certainly adds to the tank current. Do you think there would be enough turbulence without it and just several "fountain" heads?

[o2manyfish]

GBTower,

I am not shooting any water above the surface in the tank. I run my water level to the top of the acrylic tank.

You could definitely aim it at any surface. I have a several inch sand bed, and in this orientation not only do I not disturb the sand, but I also get flow pushing off the top of the tank and flowing down the corals and and the rock towards the front of the tank.

Dave B

[rspar]

Interesting, I was thinking you could run a pipe under the sand and through a piece of rock pointing up to get this effect.

[o2manyfish]

The best flow comes from the water coming above the system and falling back upon itself.

Dave B

[Fliger]

I've dove a few reefs at night that I dove during the day and I did notice an extremely SLIGHT difference in turbulence. But not anything near the same as turning a CL on and off. Mojodeli has the Tunze system with a night feature - I wonder how much that cuts it back.

One other thought, I was at a guy's house that has an AQ2 hooked up to a laptop, and he was telling me that when you monkey with anything that has to do with water movement, your OPR and I believe ph are affected, and not as slight as you would think. I'm hooking my AQ2 to a laptop in a couple weeks and I'd like to check that out.

I think we have a tendancy to anthropomorphize our fish and corals. Someone mentioned that corals don't have the luxury of moving - that's because they don't NEED to move, they've evolved in a manner that they can cope (like closing up) - or they NEED the current, even while they're closed. For fish, unless you have an EXTREME amount of flow with VERY LITTLE rock, they'll always find a way to hide.

Anyway, just my thoughts - I have to run.

David

[striker3636]

Had to add my 2 cents...
I'm not a very experienced reefer, but I am a very experienced diver...
I have logged thousands of dives both in private and professional life, hundreds in the reef environment. I have also been fortunate enough to dive on quite a number of different reefs in different parts of the world including the Red Sea, Carribean, and South America. I have noticed a considerable difference in water movement on shallow reefs (say 20 feet and less) between day and late night diving. Most of this seems to be tied to wave activity. All things being equal, the seas generally calm down at night, as do the winds, likely because of the loss of the heating influence of the sun etc...
Most shallow reefs get a lot of their water movement from surge caused by waves changing from deep water to shallow, and often breaking at the upper reaches of the reef wall. Often you can identify a reef from your boat on a rough day by seeing the waves breaking, or changes in the scope of the waves. The water movement in shallow water reefs changes daily based on weather and wind patterns, etc... everywhere from calm to highly turbulent. And the creatures on the reef adjust daily to the differences. Deeper water reef environments, like in the Red Sea, are not as much subject to these changes, and are more controlled by currents that stay more consistant.
Many of the corals in our tanks are shallow reef inhabitants, hence the need for bright lighting, etc. They definitely get varied current based on wave surge.
I personally turn off my closed loop at night and run with just the main pump. I suspect this is the rationale of a lot of the wavemaker manufacturers offering a night mode as well.
Bottom line, use what works for you. If your corals seem happy with reduced nighttime flow, as do mine, use the little bit of electricity you save to buy them some friends.