Please help, Microbubbles, simple system-diagram inside...

[Ian]

Tank is a standard 90 gallon. Ive always had a microbubble problem and Ive tried everything from adding baffles to changing pumps to replacing the plumbing from soft to hard. If I turn the skimmer off, the bubbles are still there. The extra baffle is positioned to protect the return intake even more than a standard vertical baffle. Ive changed from a panworld to a mag 3 to the eheim 1260 thats in there now. The most recent thing Ive done was remove the barbs and soft tubing and replaced with PVC and glue thinking there were micro bubbles coming into the return line.

Here's a diagram of the tank as I said its a standard 90, ATB medium skimmer, Eheim 1260 return... Please ask any question and provide any suggestions that you think may help...

 

[Ian]

waterline in the sump is just below the top of the baffle and kept there by my ATO...

 

[revhtree]

Have you tried filter socks on your return lines?

 

[Ian]

Have you tried filter socks on your return lines?

It helps some but the way it's set up, I shouldn't need them.

I really don't want to use socks either...

 

[Gimili the Great]

could the angle of that last baffle cause a water fall type effect and cause the water to bubble slightly before entering the pump?

 

[Ian]

there's no water drop off. Maybe 1/2" drop at the most because the ATO keeps the water level consistent with in 1/2".

 

[mevstheworld]

is your drain hose(from tank) submerged in the sump? mine is around 2" under the water level in the sump and has baffle to go over before entering the main chamber. is your drain tube to big? maybe use a smaller diameter, or slow down your return pump by putting a T in the return line and adding a gate/ball valve. hope this helps...

 

[EliteReefs]

it there is ANY drop off of the water prior ro the return pump you will be getting micro's. does not take much at all.

also i would add a sock. what reason do you have for not wanting a sock?? they are a great!!

what about your return, how is that set up? that can also introduce micro's

how about your skimmer return? does it have a fliter sponge on the outlet?

 

[MikeB]

Personally not a fan of the baffle design. For one they look like they are gapped to far apart,. I like baffles to be 3/4" apart. If they are to wide then they will not perform like their supposed to. What does a slanted baffle gain you?

 

[AZDesertRat]

I too use the over-under-over baffle design but they are closer together and all are vertical, I also have the center baffle gap closer to the bottom so more bubbles get sheared off at the middle baffle.
What size plumbing is on the pump, both suction and discharge? Any fittings or restrictions?
Have you tried turning the skimmer so the exit if further away from the first baffle, I know you aid this is not the source but it may help.
One thing I did to help reduce bubbles was use a piece or 1" ID reinforced clear tubing on my overflow to the sump. Its shaped like a long gradual 90 dgeree bend or sweep and lays horizontal along the bottom next to the skimmer, it gave me a much smoother entrance to the sump and bubbles disappeared.

 

[Yellowtang]

Does the Weir have a stand pipe or does the water fall all the way to the bottom of that section. A Durso stand pipe or a perforated pipe with sponges could help, the sponge version will create more maintenance because of cleaning the sponges regularly.

JR,

 

[KingRicky]

You could try placeing something in the baffle area like a sponge or better, rock rubble. This would trap any bubbles that would normaly go through. If you use a sponge, it would need to be cleadned out regularly, that is why I would use rock rubble.

 

[Psychographic]

Personally not a fan of the baffle design. For one they look like they are gapped to far apart,. I like baffles to be 3/4" apart. If they are to wide then they will not perform like their supposed to. What does a slanted baffle gain you?

How do they not work properly if spaced farther apart? IMO the only effect of them being wider would slow the velocity of the water flow which in turn should allow the bubbles to rise easier.

I'm curious to your theory on this.

 

[wishntoboutside]

ian, just wondering if you have some salt creep around the ehiem pump. they are great pumps but sometimes connecting it to an hose or pipe is a pain. i have had to put two or three clamps on the return hose to prevent air bubbles on a few set ups. the ehiem twist lock things are nice but sometime a simple female threat like a mag drive makes an easier instal. good luck and such.

 

[Sikryd]

I would be willing to bet the pump is cavitating for whatever reason. All it takes is a little air in the there, and it will perpetually send micro bubbles out. Sometimes I turn my return off, let it fill up with water, then turn it back on. This usually works.
I would also check all your lines to make sure they are sealed right. I would assume something is wrong with the plumbing portion, if it has done it will all three pumps.

 

[AZDesertRat]

I think the idea with baffles closer together is it forces the water to chage directions more abruptly causing it to release the entrained bubbles. If it meanders through it holds on to the bubbles even though it has more transit time.

Cavitation is why I asked the question about the plumbing arrangement.

 

[Ian]

it there is ANY drop off of the water prior ro the return pump you will be getting micro's. does not take much at all.

how about your skimmer return? does it have a fliter sponge on the outlet?

no drop off, no sponge on the skimmer outlet

Personally not a fan of the baffle design. For one they look like they are gapped to far apart,. I like baffles to be 3/4" apart. If they are to wide then they will not perform like their supposed to. What does a slanted baffle gain you?

The slanted baffle covers the return. If bubbles made it into that chamber, they wouldn't back flow against the current...

Does the Weir have a stand pipe or does the water fall all the way to the bottom of that section. A Durso stand pipe or a perforated pipe with sponges could help, the sponge version will create more maintenance because of cleaning the sponges regularly.

JR,

there is a standpipe

I would be willing to bet the pump is cavitating for whatever reason. All it takes is a little air in the there, and it will perpetually send micro bubbles out. Sometimes I turn my return off, let it fill up with water, then turn it back on. This usually works.
I would also check all your lines to make sure they are sealed right. I would assume something is wrong with the plumbing portion, if it has done it will all three pumps.

this is the 3rd pump Ive used and 2nd plumbing job. All that remains from the 1st plumbing is the bulkheads and I just made sure they're tight.

I also just shut down the skimmer, removed the locline on the returns and added a sock... still there :( There is no drips or salt creap anywhere on the plumbing...

 

[ptownreefer]

Ian,

It is possible that the elbow on the pump intake side is causing some cavitation. Can't say for sure but I have seen that happen before.

 

[Sikryd]

Ian,

It is possible that the elbow on the pump intake side is causing some cavitation. Can't say for sure but I have seen that happen before.

+1

From this happening to me before - I have found that any type of air or bubbles on the intake of the pump to be the problem.
Like you have found out - finding the source of it can be a nightmare.


I forgot to look at the picture - do you have a ball valve on the outlet of the pump?
If you don't - I would guess this would solve your problem. It did mine -
I throttle my pump back with it. It puts pressure on the pump so it is constantly "pushing" and not free wheeling, which prevents cavatation.
At least that was my theory from my hydraulic days. It worked for me.

Its nice when you solve problems like this, but boy is it a pain till you do!

 

[Sikryd]

Okay - just looked at the picture.

I would put a ball valve in between your pump and return heads, and throttle it back to see what happens. It doesn't have to be much at all, just a little will cause it do only pull water, and purge the air that is trapped in their now.