Enhanced Sump Design - Baffle Configuration

[abcha0s]

We've been experimenting with a slight variation on the way in which traditional baffles are installed in a sump. I have a theory as to how they work, but wanted to hear what others think of the idea. If it's generally accepted as a "good idea", we will probably incorporate it into all our builds - if not as a standard feature, at least as an option.

Here's a traditional baffle design:



The third baffle will always sets the water level. With the first baffle set at the same height, there is only a thin layer of water going over the top. This creates a strong undertow as the water concentrates and is then forced downward. This current can (and does) pull micro bubbles with it. There is also a small residual current that travels back potentially pushing micro bubbles into the downward current.

Here's a modified baffle design:



The idea behind a shorter baffle is to allow the micro bubbles to collect on the surface and to create a gentle downward current so that the force is insufficient to pull the bubbles along with it. A wider flow produces a weaker current.

Here's how this might look:



In many of our sump designs, the water does not follow a standard end-to-end flow. This sometimes means that the channels are narrow thus increasing the velocity of water flow.

Any thoughts? Does the theory hold up?

- Brad

[banditpowdercoat]

That is how I make my sumps too The thinking is correct. The 1st baffle being shorter so the water doesnt 'tumble' over it and add more bubbles. Working great for me as I have a lot of bubble entering my 1st sump chamber, but none get past the baffles

[reefwars]

ive always been curious and i could be wayyyy off here but if you were to take your first baffle and create knotched teeth kinda like an overflow has with maybe 1/8" spacing between knotches ,would the small spacing help in bursting or dissapating the small bubbles?? or would it create more bubbles??

was just curious as ive thought about doing it before but never ever tried it

[banditpowdercoat]

If there is no waterfall through the teeth, then it wouldnt create more bubbles. But breaking them up, no. If the bubble is under the water, nothing other than it coming to the surface, will get rid of it. Larger bubbles rise and 'pop' faster than tiny bubble. Tiny bubbles can be carried down with the current much easier. That's why Microbubbles can fill a tank so easy. So, if the teeth were to chop up the larger bubbles into smaller ones, then in effect, it would make it worse.

[mark]

might expect the extra turbulance in the first drawing would help microbubbles being driven out and also increase aeration of the water. Really though don't think there would be a huge advanage of one over the other.

[Lampshade]

I have that setup right now in my sump. I needed to raise the water level in my skimmer chamber a bit, so i added an extra 3/4" to the last baffle. You are very right with no turbulance in the first chamber, seemed like a good idea, didn't notice a change because i had no bubbles before and none after. When i had low flow it worked great, I now have 2500+gph going there, and have micro bubbles everywhere... but no hair algae.

If you have the water level close to that height in the return chamber then the raised baffle is great, mine lifted the flowing water another 3/4", creating more waterfall, creating more bubbles. If you had another "down" baffle you could get rid of this. It's what i plan on doing shortly, but need to figure out how small to make it so that it's functional