leave empty 1 of 3 UGF uplifts as "skimmer"?

[HelplessNewbie]

Before adding a water pump/powerhead to the 3rd of my under gravel filter (UGF) uplift pipes, I noticed that surface water was being sucked into it. I am guessing the two other uplifts with airstones were already creating enough suction.

I was wondering if it make sense to leave the third uplift empty, and use it like a surface skimmer if I put a ring around it to prevent small inhabitants from getting sucked in?

Will I be undermining the mechanism that makes a UGF work?

Edited April 11 by HelplessNewbie

[HelplessNewbie]

Mods, please move this to Experiments.

[HelplessNewbie]

@Pepere do you have input on this?

[Pepere]

Water is going to take the path of least resistance.  If it flows down the third uplift tube easiest, your flow through the substrate will be reduced.

a few inches of coarse gravel is not much in the way of restriction.  Fine sand would provide more…

I would not be inclined to try to get my ugf plate system to provide surface skimming in addition,

[HelplessNewbie]

On 4/11/2024 at 7:03 AM, Pepere said:

Water is going to take the path of least resistance.  If it flows down the third uplift tube easiest, your flow through the substrate will be reduced.

That's what I was thinking. I am keeping the mini-powerhead attached to it.

Edited April 11 by HelplessNewbie