First Overflow/Sump Problems

[lines_michael]

I put in a overflow box and DIY sump that I built last night. I think I found my limit to being frustrated and learned what micro bubbles are.

Here are my questions:

There are tubes that hang over the overflow box that are U-shaped. One end is shorter than the other. Right now the long side is out and the short side is in. It is working but I am not sure if it is right because there is a lot of bubbles coming out of the bottom of the overflow pipes. Which end is supposed to go on the intank side and which is supposed to go on the outside of the tank?

There is no air in the syphon tubes but the turbulance in the overflow box is sending air down into the sump along with the water. Is this fixable?

Help!!

 

[1F2FRFBF]

I've always understood that if you're draining water the longer side should be your outlet (think of when you siphon out for a water change), so it sounds like you have that part OK.

As far as your overflow, maybe try adjusting the water level?

I have one of these , and it took a little tweaking before it quieted down, plus I think they also go through some kind of break-in period.

 

[sjm817]

You will always pull air down an overflow of any type. There are ways to deal with the bubbles. How big is the display, sump and return pump? Is the sump baffled?

 

[lines_michael]

its a 75 gallon tank, 29 gallon sump, (2) 1" overflow pipe inside overflow box (1200gph I think), return pump is 1250 at 0 head. I have ball valve on each 1" overflow pipe to regulate that if needed.

Sump is not baffled.

 

[sjm817]

The problem is
1) too large a return pump for that system
2) no baffles in the sump.

The easiest fix is to put 100 micron filter socks on the drains.

 

[lines_michael]

Sorry, yeah there are baffles in the sump. I thought you were asking about bulkheads in the sump.

There are 4 baffles. Input-->Baffle--> Refugium-->3 baffles for bubbletrap-->Return. I placed the bubbletrap according to melevsreef. Won't the water dropping over the last baffle into the return section cause unwanted bubbles too?

I shut off my new euroreef RS80 skimmer and 75% of the bubbles went away. The skimmer hasn't started collecting yet (10-12 hours), so I probably down have it set up right yet.

I also put a ball valve to reroute water back into the refugium, instead of up into the tank. I only have a small amount of water rerouting at the moment. Last night I had to keep adjusting the rerouting ball valve and the overflow ball valves to find a happy medium that would keep syphon up top and not run the return section completely dry.

What ratio return pumpverflow is good? I'm trying to maximize my tank flow.

 

[sjm817]

You should not have ball valves on the drains, especially with HOB overflows. You are asking for a flood. Only use the ball valve on the return to control flow.

IME, baffles are pretty close to worthless to control microbubbles. The bubbles are too small and not buoyant enough. They sail right through a bubble trap.

 

[ljosh]

I had bubbles from the water falling over the last baffle into the return so I changed it so that there where 4 baffles and the water went under the last baffle. over under over under

 

[lines_michael]

ljosh: I will give that a shot. I actually ordered 5 baffles and have an extra that I can put in.

sjm817: I put them there thinking that it may help during a water change or maintenance. Should I just leave them wide open? I closed them a little because it helped with the turbulance in the overflow box and air coming through overflow pipes into sump. I did almost have a flood though last night. LOL

Any advice on little tricks that will help prevent issues when the power goes out? I have read a few nightmares.

 

[sjm817]

Keep the valves wide open.

Bubble traps work on the principal that as water is travelling downward, buoyant bubbles float up to the top. For them to work, water has to move slowly through them meaning:
1) spaced far apart (not 1") as possible
2) as wide as possible
3) as tall as possible
4) low return pump flow

All that being said, tiny pinpoint micro bubbles will be carried right through anyway since they are not really very buoyant.

 

[Toddrtrex]

One additional thing to consider is (and this is assuming there isnt a ton of mircobubbles) is that the amount will go down once the pipes get a nice slime coating. I just made a 10 gal sump for my 29 gal, the first couple a days I had some microbubble that stopped.

 

[lines_michael]

Wanted to say thanks for all that posted answers. The additional baffle in the bubble trap removed the rest of the micro bubbles and it is as clear as it has ever been.

The skimmer must not have been broken in yet, it stopped with the micro bubbles after a couple days of operation.