closed loop/micro bubbles

sri3850341

sri3850341

Member
1 of my closed loops is shooting micro bubbles.nu-clear media canister filter with gen x pcx40 pump 1 ball valve on intake and
1 ball valve on return..i am puzzled as to how this can be???there is no water dripping from lines..this happened yesterday when i was doing water change.any ideas??
can the pump suck air?is very annoying.it has been doing this since yesterday at noon.when it first turned on it was real bad almost to the point of not being able to see accross the tank.now you can barely see the stream of bubbles but they are
there..please help thanx
shane
 
michaeltx

michaeltx

Moderator
you might have got an air pocket stuck in the pipes if you took it below the lines or it could be the pump and joints leaking alitle bit of air. just because its not leaking doesnt mean that there isnt a leak in the lines it may be just enough to let air in.
if you can shut the line off try turning it off and then back on it may be enough to jolt out any air pockets that are stuck in the line.
Mike
 
michaeltx

michaeltx

Moderator
you have to trace back the line that the ar bubbles are coming from and check the connections. if youhave any elbows that the ideal place for air pockets to develope. also check the pump if its loose then it can cause bubbles to be thrown out.
do you have more than one line coming from the return pump?
and if so is there only on of them throwing out the bubbles?
Mike
 
bang guy

bang guy

Moderator
Turn the ball valve on the output side to slow the flow a little bit. If the bubbles stop then your impeller is cavitating and there's no leak.
If the bubbles continue even when the waterflow is restricted on the output side then it's possible you have a pinhole leak. I find pinholes by brushing PVC glue around all of the connectors until it stops.
Always leave the input side wide open when the pump is running.
 
sri3850341

sri3850341

Member
ok..if i shut off the intake with the ball valve wait about 10-20 seconds then turn it back on i can hear a little rush and the return spits out alot of bubbles for a couple seconds then returns to a fine mist of bubbles..my return is a 1.5 bulkhead fitting
90 then 10" to ball valve then approx 20" then 90 to canister
out of canister into pump then return..when i shut off the return ballvalve for same time you hear and see nothing but water breaking the surface and the same fine mist of bubbles..so i do believe it is the intake side..can a ball valve pull in air??
 
sri3850341

sri3850341

Member
Originally Posted by Bang Guy
http:///forum/post/2565171
Turn the ball valve on the output side to slow the flow a little bit. If the bubbles stop then your impeller is cavitating and there's no leak.
If the bubbles continue even when the waterflow is restricted on the output side then it's possible you have a pinhole leak. I find pinholes by brushing PVC glue around all of the connectors until it stops.
Always leave the input side wide open when the pump is running.
the pump is approx 3yrs old..what causes cavitation?the other pump is the same but 2 months old..no probs with that loop
 
sri3850341

sri3850341

Member
Originally Posted by Bang Guy
http:///forum/post/2565171
Turn the ball valve on the output side to slow the flow a little bit. If the bubbles stop then your impeller is cavitating and there's no leak.
If the bubbles continue even when the waterflow is restricted on the output side then it's possible you have a pinhole leak. I find pinholes by brushing PVC glue around all of the connectors until it stops.
Always leave the input side wide open when the pump is running.
the bubbles do go away if the ball valve on the return side is
turned back approx 1/2
 
bang guy

bang guy

Moderator
Cavitation is caused when you have a fairly powerful pump that has a restriction on the input side. The impeller creates a vacuum bubble because of the restriction and the vacuum pulls dissolved gasses out of the water. The result is a fine mist of these gasses that are no longer dissolved.
 
sri3850341

sri3850341

Member
bang,running 2 closed loops..4 bulk fittings 2 top left/right returns and 2 middle right left intakes.each line has ball valve.
2 nu-clear filters,both systems are independent of each other
one filter is bio disc other is pleated filter.pleated filter loop is the one giving issues only started yesterday,this is the side with the old pump (both gen x pcx 4).intake side of each is 1" return on both is 3/4..
 
bang guy

bang guy

Moderator
Originally Posted by sri3850341
http:///forum/post/2565203
bang,running 2 closed loops..4 bulk fittings 2 top left/right returns and 2 middle right left intakes.each line has ball valve.
2 nu-clear filters,both systems are independent of each other
one filter is bio disc other is pleated filter.pleated filter loop is the one giving issues only started yesterday,this is the side with the old pump (both gen x pcx 4).intake side of each is 1" return on both is 3/4..
Can you run the canister without any filter in it? I'm wondering if the pleated filter is restricting the flow too much. If there are no bubbles when the loop is running without the filter in place then you have your answer.
Can these be used on the output side of the pump? Probably not but I just thought I'd ask.
 
sri3850341

sri3850341

Member
they are installed as per the manufacturer instructions,so dont know if and why not on the return side..have not cleaned the filter yet because of establishment was going to do the one in question next weekend then the other the following week,so as not to aggravate bio's.. do have sand and it does get kicked up from aquascaping and such gets sucked into the intake.using bulkhead screens,but still gets sucked in..the pleated filter looks
dirty but can still see "stuff" inside moving quite well,(circulation)..
FRESHWATER IS SO MUCH EASIER!!!
 
bang guy

bang guy

Moderator
Rinsing the filter in saltwater will clean it and not affect the biological organisms living on the filter.
 
bang guy

bang guy

Moderator
Just shaking it underwater will remove most. It doesn't have to be perfect.
Earlier someone mentioned a damaged impeller. That would make cavitation more likely.
 
sri3850341

sri3850341

Member
ok,pulled the filter and still bubbles..shut the pump down and restartred,so bad i couldnt see accross the tank when restarting the pump!!!!i feel so bad for the fish,dont know what to do
i guess a new impeller to start..ihope my fish make it through the night..i'm about ready to give up.got a manderin goby but i dont think there are copepods yet so he'll probably starve to death.the clown and yellow tang seem good.snails i think they could care less....water tests ok o ammonia 0 trites 20 trates
 
You must log in or register to reply here.
Top