[marinelife]

hey all, I just finished my closed loop system and am getting bubbles out of the output. I am using a AmpMaster 3000 with 2 1" inputs and 1 1.5" input. the output is 1 1.5" and one spray bar with 1.5" open on the end. All the plumbing is 1.5" Thanks PS the AmpMaster is not making one noise, it is a great pump

[Ltspd]

If it is a true closed loop system, where it never is exposed to air then you have a pinhole leak around one of your pvc joints. You can solve this by swabbing each connection with more pvc cement.

It may also be cavitation. You are drawing 3.3378 sq./in of area and from what I can figure 3.534 sq/in of output area which is close enough to equal. But, are you using lots of 90's? Sharp bends? anything that might cause the water to slam and produce bubbles? What is the head pressure of the pump? You may also be pushing too much water thru the wholes system, in the form of gph, which may be causing the cavitation.

[marinelife]

I have 2 90s which was all I could use. The tank was placed close to the wall when I put it up. I did not plan for this type of system. There are also 2 45s on the output. I am going to try and get something different to use instead of the 90s but for now that is what it has to be.

[Ltspd]

Have you tried throttling back the AM's? It may solve your problem.

I run (2) on my system but due to the high heads I dont have the full bore they are capable of. On my closed loop I am pushing about 6ft plus the friction loss in the pipes, I would guess I am going around 2800 gph. I have no bubbles.

[marinelife]

thanks guys for the replies, but somehow I got the bubbles to stop. I had stopped the pump for a while then re-primed it and it made a few bubbles at the beginning but has stopped.

[Ltspd]

You may have tightened a fitting on the pump and stopped the suction of air. Glad you solved it, they ae annoying.