Stop the micro bubbles!!!

melev

melev

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Guys, one of the standard complaints I come across are those darn micro-bubbles you see in your main tank. They obscure the view, and can ruin picture-taking sessions.

So the first thing you should do is see if your return pump is too powerful for your setup. All you need is a pump that moves 3x to 5x the volume of the display tank. So if you have a 100g tank, the return pump only needs to move 300 to 500 gph. If you have a pump that moves more water than that, you might be encountering this problem. There are a few solutions:

*Get a smaller return pump.
*Get a longer sump, which allows more time for water to travel and let's the airbubbles rise and pop.
*Install a bubble trap before the return section in your sump.
*Attach an elbow to the return pump's intake to suck water from the bottom 1" of water in the sump.
*Put LR in the return section to act as an obstacle to inhibit the bubbles from entering the pump.

Or my favorite...

Stop the bubbles at the source. Thus, the Bubble Tower concept.

So here are a series of images to help you create your own bubble tower to put in your existing sump, as it may be too late to glue one in at this point. Many sumps that I build have a corner tower installed, but here is a sump that needed a little more flexibility.

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This bubble tower is easy to remove, or to place where the owner needs it to be. It is constructed with 1/4" extruded acrylic and Weld-On #4. The tools I use are listed on this page, so take a look if you haven't seen it before: http://www.melevsreef.com/tools.html

The principle behind the bubble tower is to create a tall column that the tank's drain line will pour into. If the tower is filled with live rock rubble only as high as the water level it is standing in, the bubbles will boil off within the walls and reduce them dramatically. The rubble should be fully submerged under water, with none of it exposed to air.

Here is a brief 1.2 meg video of a bubble tower doing its job: http://www.melevsreef.com/video/trapped_bubbles.wmv
 
In the case of this sump, the water level in the skimmer section is 12.5" deep, so the bubble tower had to be taller. I made it 16" tall, as the sump walls are 14" tall. I want to not only break up the bubbles from the drain line, but also keep salt creep / spray to a minimum.

This is not a quicky project, and I probably spent about 2 hours making this one. I wanted it to come out nicely.

The bubble tower has a base piece, so that you can remove it from the sump and not have the rock rubble pour out all over the place.

There are teeth on three sides, not all four. The side that does not have teeth faces the next section, to avoid releasing tiny bubbles prematurely. It is better to release them further away so the travel time is maximized.

Several inches of this tower will be full of air, and that is fine. It is made to keep the bubbles bursting inside the box. Below is an image with the water level sketched in.

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The lid is removable.

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The opening is 2" wide, which will accomodate most plumbing (rigid or flexible). A bulkhead could be used, or a piece of thick rubber to act like a splash guard.

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If you have a tight seal where the plumbing goes into the lid, the bubble tower must be able to vent out some of the air that is accumulating.

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I made the lid with four sides to help force and salt spray to pour down into the sump and avoid spattering the walls of the cabinet. The lid fits snugly, but not air-tight.

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The teeth are cut with a 3/8" router bit, every 3/4". They are about 1.5" tall. Please note, in the image below, I put the smooth side toward the viewer, but in reality the tower would be installed with the smooth side facing the bubble trap of the sump. I wanted you to be able to see the side with no teeth as easily as possible.

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Here it is in the proper position. Behind it is a small 6" stand for a skimmer pump, in case you were curious.

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One more perspective to help you see its design. The box is roughly 3.5" x 3" x 16" tall.

It is taller than the sump, which is fine. Even if the box were to overflow for some reason, it would pour down the walls into the skimmer compartment.

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Now, do you have to do all this work? No! You can buy some 3" PVC that is 16 to 18" long, drill some holes near the base, stand it up in your sump's skimmer section and fill it up with some LR rubble. Insert the drainline, and you're done.

I hope this thread helps some of you. As always, if you have any questions, just ask.
 
If you plan to change them out regularly (every 2 to 3 days), that is another easy alternative. However, if you leave them and ignore them, not only will they clog up and overflow, but all the food that trap in them will break down and rot in the water 24/7.

I only recommend using filter socks for heavy cleaning sessions and siphoning the detritus from the sump. The rest of the time the water flows freely into all sections of the reef. No mechanical filtration is necessary.
 
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