Day vs Night Flow

[LFGJP]

Yes, the ocean doesn’t, however in tropical climates sunlight causes heating and this heating increases wind….so daytime wind driven currents are generally stronger.

With this being said, does the temp changes (or if we were to change it during the night) would that help with coral growth? Fish health? Are there any studies on this? I’ve always wondered this…
In the natural reefs the temp drops during the night… but seems like no one talks about how to mimic that.. maybe it’s just a random useless thought by me haha!

 

[Hairyteeth]

With this being said, does the temp changes (or if we were to change it during the night) would that help with coral growth? Fish health? Are there any studies on this? I’ve always wondered this…
In the natural reefs the temp drops during the night… but seems like no one talks about how to mimic that.. maybe it’s just a random useless thought by me haha!

Get even nerdier change the temps daily and seasonally, make a moon cycle the aligns with the actual moon cycle…..make your lights honest to west
Make everything spawn

 

[56longroof]

I've heard opinions about it from both sides for a while now. I personally don't see the need since 99% of the corals we get are tank raised. Also if you have enough rock work the fish have plenty of places to hide. Plus the constant surface agitation helps with gas exchange 24 hours instead of 12 or 14.

 

[EricR]

That was my guess as well. Plus I always assumed corals don’t need as much flow when there is no photosynthesis happening, but that’s also just a guess

In nature there would be 2 high/low tide sequences about every day.
I assume that high tides potentially mean less turbulent current flows for shallow water organisms that we tend to keep in reef tanks.

So I speculate that we're giving at least some semblance of that -- we're just mimicking that on our own 24 hr/day schedule.
*I'm fine with that

 

[Bartanto]

Probably overkill (or underkill?) but this is what I set and forgot a long time ago. Fish or corals haven’t complained yet…

 

[Johnd651]

Probably overkill (or underkill?) but this is what I set and forgot a long time ago. Fish or corals haven’t complained yet…

It's random.. I'll say that

 

[Marinus]

I set my Nero 5 schedule to have very low flow at night. The fish seem to sleep better.

 

[MnFish1]

Yes, the ocean doesn’t, however in tropical climates sunlight causes heating and this heating increases wind….so daytime wind driven currents are generally stronger.

Do you have a reference for this - and how significant the currents in the ocean / reefs differ? Aside from anecdotal articles on other reef sites (and this one) - I haven't seen any clear conclusions. Then when one considers that the currents in the ocean are magnitudes higher than in our tanks - intermittently - it begs the question - is a mixed flow (i.e. non-directional) - alternating better than the call to decrease flow at night. In our tanks I think it causes no improvement - and possible detriment (though not alot of detriment). Frankly I think the more flow the better (non-directional/variable every several minuets). I am more a fan of Gyres than wave makers - and perhaps that is also a difference. Interested in your perspective

 

[MnFish1]

In nature there would be 2 high/low tide sequences about every day.
I assume that high tides potentially mean less turbulent current flows for shallow water organisms that we tend to keep in reef tanks.

So I speculate that we're giving at least some semblance of that -- we're just mimicking that on our own 24 hr/day schedule.
*I'm fine with that

Agree - that would be the maximum flow - however there is always flow - and its often much stronger at the minimum that what we have in reef tanks. However. not arguing - it's an intriguing discussion. I tried it - it saved electricity - not sure it help (in fact probably hurt) coral

 

[Uncle99]

Night is for rest.
I tone it way down between midnight and noon.

 

[CHSUB]

Do you have a reference for this - and how significant the currents in the ocean / reefs differ? Aside from anecdotal articles on other reef sites (and this one)

I read it on a NOAA site but it was more about hurricanes impact on reefs. Also I remember reading it in a few books. You will have to take my word that I’m not making it up, because not worth me searching for hours for something that is very insignificant.

In our tanks I think it causes no improvement

I think most, including myself, agree that it make no difference at all, besides just mimicking something that happens on ocean reefs. Maybe on ocean reef this gives corals a better chance to catch prey and during spawning the eggs have a better chance of not being swept into the vastness, I’m just thinking…

 

[kipmando]

I have 3 different pumps in my tank:

1) Nero 5 on a pulse and it slows down in speed and duration (flow) at night
2) Return pump stays the same (lagoon with 2x vca adapters)
3) wavebox stays the same

I'd say the Nero 5 during the day pushes around the most water and hence theres is a pretty noticeable step down when it switches to night mode.

So there is overall less flow in my tank at night, but hints of the same pattern as during the daytime flow.

 

[cilyjr]

Having within a 1/2 mile of the ocean my entire life, most of it, the Atlantic but the last 8 years the Pacific, and being an avid sailor most of my 50 years on the planet, there are absolutely diurnal swings in wave action due to the faster cooling and heating of the land affecting local wind driven wave action.

That however does not necessarily mean anything below the surface is calmer. It could be but also maybe not, personally, I've never really cared about day or night settings and just try to go pretty random.

I read something pretty recently about how diurnal swings in the first 10 m of the ocean is slowing coastal upwells and areas because they are getting warmer.

 

[Hairyteeth]

Don’t forget to set your pumps randomly to 100 and engage your kessil lightning mode!