Questions that need answers

[hankhill31]

I was with a reefing buddy and realized he had micro bubbles in his display and so do I different setup two different sizes only thing in common is 3/4 inch return pump my return is 2200 gph his was at 540 gph my thought is the 3/4 is making the water jet stream cause of the size and 1 inch wouldn't do it am I crazy

 

[bcavalli]

How deep were the return sections on each tank? More than likely it’s pulling air down to the return pump and sending it up to the DT. Raise the return level up and see if it stops.

 

[FutureInterest]

Could be what Brett mentioned above. For me, it was due to cavitation. I used to have it on my 180 until I swapped the hard plumbing out for spaflex.

 

[AquariumSchmo]

I don't mean to hijack this thread, but hopefully my similar issue will help lead to a resolution for you. I have micro bubbles too, but with a soft return connected to a over the rim u-tube return nozzle. I don't see any in the return section or coming out of the return nozzle, and I don't see any signs of air being sucked into the return pump. Could it be surface agitation? It is really hard to tell, but it almost looks like they are being created at the overflow as the water level sloshes about. I will do some experimenting this weekend with lowering the flow from the return pump and raising the water level in the return pump section and let you know if find the cause.

 

[saltwaterwannabe]

What style overflows do you have?

 

[AquariumSchmo]

What style overflows do you have?

Traditional overflow box in the tank (drilled).

 

[picoreefguy]

he meant how is the overflow plumbed? as in bean animal, herbie, durso or any other style. different overflows work in different ways and can give you different pros and cons. typically the herbie and bean animal are super quiet with very little bubbling (if any) in the sump and none that make it to the tank. another source to consider is your skimmer, if its not adjusted properly some of the bubbles can make out of the outlet from the skimmer and flow through your sump into the display. that happened to me back when i was using a cheapo skimmer that was hard to adjust and it would spew bubbles into the sump.

 

[FutureInterest]

You are going to get bubbles into the display from the return in a variety of ways. It often does come from a skimmer as picoreefguy says or from the overflow as brett says. Both are mitigated by simply using a bubble trap in the sump before the return pump... so long as your flow through the sump isn't overpowering this works very well. To verify whether this is the issue turn off all the room lights and tank lights at night and use a flashlight on the water before it goes to the return pump. If you see telltale sparkles or cloudiness then you know the microbubbles are already in your sump from either the skimmer or overflow. Turn off the skimmer to isolate whether the bubbles are coming from the skimmer or the overflow. You can add a filter sock to the system to mitigate if its from the overflow. If its from the skimmer then just add a sponge to the output. Another thing to consider is that if you do have a bubble trap and you are still getting microbubbles into the return pump then you need to reduce the flow as your sump is then too small for the return pump you are using.

If the water going to the return pump is clear of bubbles then the other thing to look at is going to be your return pump or return line. Both of them can cause microbubbles by way of cavitation. Typically, adding a bit of restriction on the output will help reduce bubbles from the return pump/plumbing. So if you have a valve in there try turning down the return flow a bit. Also going with more flexible tubing instead of hard plumbing will help especially if you're using 90 degree fittings.

If anyone is near me in Suwanee and needs some help, I don't mind swinging by and taking a look .

 

[hankhill31]

im runnin shadow overflow 1.5 drains 3/4 return.the return section is 8in deep external return pump 2200gph

 

[hankhill31]

oh sump is a diy 75 gallon triton build

 

[FutureInterest]

It's hard for me to tell... but it looks like you have 2 skimmers. One in the fuge and one in the return area. Normally the skimmer is placed in the section that comes from the overflow because the water in that section is always consistent. You also don't generally want a skimmer in the return area because of possible microbubbles as well... You should also put in a bubble trap. It's just one more piece of acrylic right before it goes to the return pump section.

 

[hankhill31]

ill post another pic the water the chamber before the skiimer has a trap wat goes from under to get to return

 

[hankhill31]

1st pic from far
2nd close up
3rd return side my water level is high I thought triton built the bouble trap different water passes thru to sponges after it leaves skimmer

 

[hankhill31]

this the sump layout

 

[saltwaterwannabe]

I agree with everything Jin said. A few more thoughts... If you have air bubbles entering your sump, they can overwhelm it no matter what you do in the sump. If you are getting bubbles in the line from your dt to the sump then you will need to tweek the overflow. I have 2 shaddow overflows and had to adjust the riser lengths to get them working right. I also smoothed the edges of the inserts to prevent cavitation since I am running high flow.

Ideally your skimmer will be inline before the bubble wall (if you have one). If not, and the skimmer is throwing a lot of bubbles, you can dramaiticaly reduce the bubbles with skimmer adjustments and a sock if necessary...as Jin said.

I agree it is hard to tell from the pics but it looks like you either do not have a bubble wall or the flow is overtopping the bubblewall. The bubble wall forces water downward under a baffle. As long as the flow velocity passing under the baffle is slower than the bubbles rising velocity, no bubbles will pass. This is the most common approach to removing bubbles.

If all above is not solvable, you could also put a foam filter between the skimmer and return pump..not on the pump intake or it will just suck the bubbles through. My personal preference is to not have foam filters other than on qt's due to maintenance, but it would work.

Lastly, 2200 gph is quite a bit of flow, so cavitation could be a concern if the water velocities are over a few feet per second, particularly if you have rough bends or changes in pipe size. Cavitation is caused by fast changes in pressure creating vapor bubbles. Damaged pump impellers can cause cavitation also as can combinations of inline pumps in some cases where the impeller is fed water at a rate it not designed for. Cavitation can cause damage to equipment as well.

 

[snowmansnow]

could be as simple as your skimmer pumping bubbles back into the sump