water flow direction

PapaBear941 · Mar 3, 2022

Hello All,

So I wanted to ask for some opinions, as well as input from what you personally do, as far as water flow goes.

My question is, do you all have your flow set up in tank to be disturbing the surface of the water tank level, or do you direct your flow more into the tank area. My reason for asking is I guess related to light/lighting.

Currently I have my flow in tank directed up to the surface of the water line, which disturbs the top of the water, as seen in this pic.

Is this good or bad, in your opinion? I dont know why I have it set up the way I do, other than my thought was to break up any surface film/debris that might form on the top layer, but im wondering what this does for the tank inhabitants below, as it ends up causing I guess id call it ripples, that show up on the sand bed from the light reflecting down, im using an AI Prime running a scaled down to 35-40% of the BRS recommendation for the AI Prime, and I am using a 3D Reefing diffuser. Heres what that looks like:

About my tank. Its a Fluval 52L, corals only. Zoas and LPS only. Tank has been up for about a year.

Thanks for your opinions.

FiddlersReef · Mar 3, 2022

I keep my return lines about 1/16" below the water surface, so they churn it up pretty good. And most importantly, when I shut off the return pump, they suck air in really fast and stop the siphon almost immediately.

My MP40s are obviously way below the water line, and they do all the heavy lifting for circulation in the tank. They're directly across from each other, each set to slightly different intensities so flow goes every which way as they collide.

PapaBear941 · Mar 4, 2022

FiddlersReef said:
I keep my return lines about 1/16" below the water surface, so they churn it up pretty good. And most importantly, when I shut off the return pump, they suck air in really fast and stop the siphon almost immediately.

My MP40s are obviously way below the water line, and they do all the heavy lifting for circulation in the tank. They're directly across from each other, each set to slightly different intensities so flow goes every which way as they collide.

That sounds like that probably works well for you, but it also sounds like you have a system with a remote sump, where as my tank is an AIO, and so I cant close the gap of the water going into the rear chambers to that little or the water level in the tank would end up being too high and potentially spill over.

Im hoping that those with similar AIO tanks will be able to provide their input.

I thank you for your time.

FiddlersReef · Mar 4, 2022

PapaBear941 said:
That sounds like that probably works well for you, but it also sounds like you have a system with a remote sump, where as my tank is an AIO, and so I cant close the gap of the water going into the rear chambers to that little or the water level in the tank would end up being too high and potentially spill over.

Im hoping that those with similar AIO tanks will be able to provide their input.

I thank you for your time.

Ah ok, sorry. I didn't see anything in your post saying there was no sump. I guess if I should have researched what a Fluval 52L was.

Reefer Reboot · Mar 4, 2022

With ripples on the surface (a good thing for gas exchange) the light travels through an everchanging series of convex and concave "lens" of the rippled water surface. But at the end of the day it all averages out. In the real ocean, a perfectly glass flat water surface is extremely rare.

PapaBear941 · Mar 4, 2022

FiddlersReef said:
Ah ok, sorry. I didn't see anything in your post saying there was no sump. I guess if I should have researched what a Fluval 52L was.

Its OK, no worries.

PapaBear941 · Mar 4, 2022

Reefer Reboot said:
With ripples on the surface (a good thing for gas exchange) the light travels through an everchanging series of convex and concave "lens" of the rippled water surface. But at the end of the day it all averages out. In the real ocean, a perfectly glass flat water surface is extremely rare.

And I thought about that how the water isnt perfectly smooth, but I was curious if there is a "too much" scenario.

bmkid1997 · Mar 4, 2022

I run a waterbox AIO, and put my return pumps so they move the water surface some. But I run a SPS tank so have alot of flow. I Have 2 gyres across from eachother on alternating pulsing and a jebao pointing up from the bottom of the tank. This really gets the water moving, and acts like a wave on the top. I also enjoy the look of it with my Kessil lights for shimmer. Definetly no harm in having ripples on the surface.