Changing flow at night

So,I just received and started using a wp-25 in my 40breeder and wow what a difference! I previously was using two korallia evo750's and this one wp-25 has really increased random flow in the tank.I have it set on else mode and flow looks good everywhere with the area right below the powerhead being the only place that could be called "low flow".I have the controller mounted to the outside of my stand just below the tank and at dusk with no room lights on the light sensor switched the unit into night mode.I turned on some lights in the room and it returned to else mode,pretty cool.So now my question is do I want the flow to decrease at night or should I maintain the good random flow 24/7? I can remove the light sensor and it will remain in any setting I choose,or I can leave it in and at lights out flow will become constant at the lowest speed.

 

While the tide does indeed change in nature, the shifts are consistent with the lunar cycle rather than daylight.

What most experienced folks will tell you is that it's a bad idea to lower flow at night. With the absence of photosynthetic activity, your O2 level drops enough to alter pH; reducing flow can ultimately lower gas exchange, which in turn will further reduce the O2 level causing an even greater change in pH.

 

well, there's your answer sailorguy!

 

Iused to never change my flow. till I got the pair of WP40s. now I also use night mode. I still have my closed loop setup too and now have it come on for 25 minutes and off for 5 mins during the night period. I only have a 2 hour window where it is just the night mode and the return pump. I havent seen any ill effects as of late.

I have a very random tank flow. I have a sea swirl at each end set oposite of each other. I also have the wp40s just below them aimed at center glass. one on Else, 1 on W1. then during the day, my loop comes on for 5 minutes every 25 minutes giving me an extra 3000gph boost.

Love it.

 

I was using my night sensor on my wp40 for the first month. Thought it was a neat function. It would only turn off when my house lights were off. Most of the time not till like 11:30 or 12:00. When i would look at the tank with a flashlight I had really good PE and decided to take the sensor out. Since then early in the morning before work I would look at everything and things seemed just so happy that I decided not to use the sensor. This is my personal experience and for me I am not changing flow at night anymore.

 

I have 700-1300gph mini palario 7ml on one side and a MP10 on the other of a 57gal. I use night mode with the MP10 (50% and constant) but the other stays on full. I feel like the corals and fish appreciate a change in flow overnight, In my experience tides often come in and out pretty predictably on a daily basis and I assume this is the case most places. So I will prob stick with night mode. Plus, I like to keep the flow at the higher end off what the corals can handle...so they might need the break

 

Here's an excellent article on lunar tides. One thing I found very interesting:

Most reefs are at or near the equator. With a much reduced shift between tides, this could imply that the flow is not as dramatic as we thought.

BTW, there are 2 high tides every 25 hours, so to assume the ocean is calm at night or that the tidal shifts occur at the same time every day is incorrect.

The Moon And Tides

 

Thank you all for the info.Great article Mr.Bill,that info will be good for me to try to remember when sailing as the area(deleware river) we race in is tidal and the strength of the current is always a big factor.What I was really wondering is if anyone noticed a difference in their corals by reducing flow at night.I am assuming the fish wouldn't mind it a little calmer during resting hours.I actually decided to remove the light sensor from the wp-25 controller anyway beacause it seemed to not work well,perhaps due to the location I chose for the controller.Other than that I really like this wavemaker,for someone with a smaller system that doesn't want to spend the money for a vortec I think it's great.

 

The light sensors that come with the units only work in dim lighting, not total darkness unfortunately. As far as fish liking the calmer waters, where they go to sleep I doubt they even notice a difference honestly. So it is more about corals IMO.

 

Mine went into night mode near dusk which is also when my leds ramp down but rerturned to else mode(previous setting) when I turned on some lights in the room.It then switched back to night mode when the leds had dimmed lower to near the moonlight setting but oddly returned to else mode when I turned off the ambient room lighting.