plumbing bubble troubles

[jhale]

I changed my return pump to the sequence snapper this weekend.

I used 1.5" on the intake, and 1.5" spaflex to run to the chiller and back.

It had plenty of flow, but also plenty of bubbles.
It looked like a wave crashing in the tank, all the time.

I took the chiller off line, and cut off the long run of tubing.
I'm still getting a huge amount of bubbles in the tank.

If I use a 1" line on the return will that help things, also should I
step the intake down to 1" ? It has a 2" intake and a 1.5 return.

:help:

 

[kimoyo]

Are there bubbles near the intake of the pump and how far down is the intake from the water level?

 

[meschaefer]

If you have bubbles, air must be getting into the system someplace. Check all of your connections. Do you have baffles in your sump?

I also find that when I redo my plumping, I get small bubbles in my tank for about the first week and then they seem to go away.

 

[jhale]

there are no bubbles in the return section,
there are three bubble baffles, they work well.
the intake is at the bottom of the sump, maybe 12" of water.

there is one thing meschaefer mentioned about the air being sucked in.
the intake is plumbed over the sump, not through a bulkhead. to prime the pump I used a tee fitting, at the top I glued in fitting with a threaded cap.
The cap is on tight, but I did not use any plumbers tape, so air could be sucked in through the threads, does that sound plausible? I'm not home right now so I can't check this.

also these are not just small bubbles, and they are coming out all the time, not intermittent.

 

[House of Laughter]

give it a few days before you decide to change, unless it's like a skimmer in the tank, it should go away - also, I purposefully run a bead of PVC glue on the outside of the fitting seams to avoid this issue. I totally goob it up drips and all, but it always works for me.

House

 

[junglebase]

there are no bubbles in the return section,
there are three bubble baffles, they work well.
the intake is at the bottom of the sump, maybe 12" of water.

there is one thing meschaefer mentioned about the air being sucked in.
the intake is plumbed over the sump, not through a bulkhead. to prime the pump I used a tee fitting, at the top I glued in fitting with a threaded cap.
The cap is on tight, but I did not use any plumbers tape, so air could be sucked in through the threads, does that sound plausible? I'm not home right now so I can't check this.

also these are not just small bubbles, and they are coming out all the time, not intermittent.

I have the same problem too. But my bubbles are intermittent. 3/4 going to the pump then reduced to 1/2 cause I plumbed a 1/2 union valve so that I can disconnect it if i need to before it reaches the pump. The return is 3/4 pipe plumbed going back to the tank. Is the bubble caused by the reduction of the pipe from 3/4 to 1/2 (becaused of the union valve) before reaching the pump? I need a professional opinion on this before I get rid of the 1/2 union valve and get a 3/4 instead. Ronen, Input please.....:arg:

 

[regal]

.....The cap is on tight, but I did not use any plumbers tape, so air could be sucked in through the threads, does that sound plausible?

That's certainly a possibility. The negative pressure from the intake is very powerful with the sequence pumps. If you put your hand near it, you'll know what I mean. I would definitely seal the cap and see.

 

[jhale]

give it a few days before you decide to change, unless it's like a skimmer in the tank, it should go away - also, I purposefully run a bead of PVC glue on the outside of the fitting seams to avoid this issue. I totally goob it up drips and all, but it always works for me.

House

Jim this is a ton of bubbles, almost like you can't see anything on one side of the tank.

I'm thinking there's air getting in through the cap now,
I will try your goobing method also

 

[regal]

If I use a 1" line on the return will that help things, also should I step the intake down to 1" ? It has a 2" intake and a 1.5 return.

:help:

I don't think that would help. By going down on the size of the pipes, you are just lowering the volume of flow by incresing resistance. It will only help if the flow is so high in your sump that air bubbles are going suck down from the water surface like a vortex effect. Lowering the flow will help but I don't think that's what you want to do. If your return has a ball valve on it to control the flow, by dialing it down, it'll accomplish the same thing as reducing the size of the pipe. That's one of the reasons people don't recommend a strong return pump to get high flow in a SPS tank but using closed loops instead.

 

[jhale]

ugh, okay I'll have to put back the 1.5" spaflex then, and test out the cap for air, what a pita.

I got this pump to plumb a chiller 7' away from the tank, by the time it gets back to the tank the flow is not all that strong.

but, when I took the long run of pipe off and made it a normal return length, 2400gph going through my sump was something to see. my two 1.5" drains could barley keep up with it, the water was almost level with the top of the bracing :Yikes: I did have to dial the flow down a bit with a ball valve.

 

[DEEPWATER]

Jhale ,
Thats the reason they make plumbers tape .lol

From the threads you can get air thought it.Cant hurt to put some on ,also if you have room ,Install a ball valve below the primer tee ,so you can always work on the tee w/o shutting your system down

 

[regal]

....when I took the long run of pipe off and made it a normal return length, 2400gph going through my sump was something to see. my two 1.5" drains could barley keep up with it, the water was almost level with the top of the bracing :Yikes: I did have to dial the flow down a bit with a ball valve.

Scary isn't it. I use the baracuda as a return pump. It kicks a$$.