Turning power heads off at night?

[Marcom12]

I finally have some fish in my tank (YAY!)... And wonder if I should turn off the power heads at night?.... Leaving the return pump on obviously. Or maybe turn them way down?

 

[TheEngineer]

I finally have some fish in my tank (YAY!)... And wonder if I should turn off the power heads at night?.... Leaving the return pump on obviously. Or maybe turn them way down?

I think that's what most people do, I do. All of my flow slows down at night.

 

[Marcom12]

I think that's what most people do, I do. All of my flow slows down at night.

Off? Or just turned down.... The return pump keeps some flow in the tank....

 

[TheEngineer]

Off? Or just turned down.... The return pump keeps some flow in the tank....

Oh you definitely need to keep flow in the tank. Your idea to just leave the return pump on is a good one if you can't control the speed of the wave makers.

 

[ScooterV]

If they can be turned down, I would turn them way down and not off. When off entirely live critters may move in and in the morning result in death or a jammed pump.

 

[Marcom12]

Oh you definitely need to keep flow in the tank. Your idea to just leave the return pump on is a good one if you can't control the speed of the wave makers.

My power heads controllers have a "night mode* where it ramps it down to lowest setting. Problem is, it's a light sensor and the sensor is in the stand and not reliably night and day lol.... I have my refugium light on at night so it wouldn't shut off.

 

[Marcom12]

If they can be turned down, I would turn them way down and not off. When off entirely live critters may move in and in the morning result in death or a jammed pump.

Ohhhh hadn't thought of that....thanks.

 

[Codym808]

I have wondered about this topic once before. I read up about it quiet a lot too. Like all the other threads, there's always people on both sides of the fence. There's one side of how we should give our fish a break from the flow to let them rest, which is completely reasonable.

After doing my research I've come to conclusion that our tanks still need a good amount of flow at night. I find that at night when corals (if you have some) close up, this gives the tank a chance for the flow to reach detritus that the flow can't reach during the day because the expanded corals are blocking the flow. SPS at night also extend they're polyps more which I assume is to catch food in the water column.

So the choice I've made is to meet in the middle. I do maintain a good amount of random flow in my tank but turn it down by 10%-20% during the night to also let the fish rest. The fish will find sleeping areas where the flow isn't too strong for them so that they can get some sleep. The corals are still getting flow to keep them moving and not remain stagnant. Hope this helps you with your decision!

 

[DivingTheWorld]

I personally just go by my experience as a diver. The ocean doesn't turn off at night. So I run my MP40s at 90% reefcrest 24/7. I have noticed my fish are more muscular as a result.

 

[Tennsquire]

My flow pumps go down at night to like 30% as they're on a light sensor. I do run my lights at night (so I can enjoy the tank when I'm at home), so my "night" is actually during the day.

 

[Marcom12]

Thanks everyone

 

[fernalfer]

Not sure why people try to do the opposite of their natural habitat. Do you guys believe the ocean says "oh its night time let's slow down the currents". The ocean never slows down so why should your reef tank.

 

[MrObscura]

I wouldn't lower anything at night. I don't. Flow helps corals intake nutrients and export waste, as well as keep them clean of detritus. I see no benefit to lesson this at night.

Fish will find a lower flow area to settle down for the night.

Imo night modes are just marketing.

 

[fernalfer]

I wouldn't lower anything at night. I don't. Flow helps corals intake nutrients and export waste, as well as keep them clean of detritus. I see no benefit to lesson this at night.

Fish will find a lower flow area to settle down for the night.

Imo night modes are just marketing.

Agreed!

 

[Mr.Z]

I don't know if this is actually the case, but it is possible that slowing down the pumps actually does more closely replicate the "real world" for fish. Aquariums are confined spaces and even if there is a lot of rock in the tank, it might be hard for fish to escape flow. Because oceans are so vast and the underwater terrain is much more complex, fish can more successfully seek out sheltered, lower flow areas during night time.

...again, I don't know if any of this is at all true. Just a hypothesis.

 

[ca1ore]

Keep in mind that the lack of photosynthesis at night means less oxygen in the water (respiration occurs 24/7) so proper surface exchange is MORE important during the dark hours. I don't recall seeing water movement/surge data from natural coral reefs, but if my personal night diving experience is representative, surge doesn't magically stop at night. I do slow my vortech pumps a bit a night (mostly I just stop them running in pulse mode) , but only a bit.

 

[Codym808]

In my experience with the ocean and fishing, during the day its a lot more windy which causes the ocean to have choppy waves. The choppy waves make the water near shore and on the reef pretty rough.

At night time the winds die down and the ocean is more calm with a more gentle up and down movement of the water. The waves aren't breaking as hard over the reef and even the diving is a lot easier since you're not being thrown around and slammed. Not saying there is no current at night, but IME the ocean slightly calmer at night.

*Edit* Unless there's a storm rolling in, then the ocean is rough all day and night.

 

[wesman42]

In my experience with the ocean and fishing, during the day its a lot more windy which causes the ocean to have choppy waves. The choppy waves make the water near shore and on the reef pretty rough.

At night time the winds die down and the ocean is more calm with a more gentle up and down movement of the water. The waves aren't breaking as hard over the reef and even the diving is a lot easier since you're not being thrown around and slammed. Not saying there is no current at night, but IME the ocean slightly calmer at night.

*Edit* Unless there's a storm rolling in, then the ocean is rough all day and night.

I was under the impression that currents are more slowly affected by wind than the density of the air or temperature. Doesn't that mean that the wind could die down but currents persist to an extent?

 

[Codym808]

Well in the deeper sections of the reef, maybe like >15' it seems that the flow/current remains pretty constant throughout the day and night where the waves don't really make too much of a difference. Where the waves break on the shallow reef is where it feels more rough during the day to me compared to at night. This is just my experience though and those shallow reefs is where I see SPS and zoas, not really any lps or large softies.

 

[Butuz]

You need some flow at night. My bubble gum monster chalice and sun coral actively feed at night. Some acros extend way out as well, so some like nighttime and need flow.