Overflow box not keeping flow

[FRANK48]

I would say it’s flow consistency. Overflow with syphon needs consistency. Maybe consider AC pump

Sorry to ask but what is an ac pump ?

 

[Dan_P]

Yes I am and I’m not sure how to get them to go away

I have found two ways bubbles tend to become trapped: flow rate and a dirty siphon.

I think air bubble formation in an overflow system is normal. Water flowing through an obstruction or over an obstruction or just falling into water makes little bubbles. Generally, these little bubbles just pass through the siphon. If the water flow is slow, bubbles can accumulate to form a bigger and bigger bubble which is more likely to leave the stream and come to rest at the top of the siphon.

Another factor that seems to influence big bubble formation is the growth of a biofilm and algae on the inner walls of the siphon. Bubbles may adhere slightly better to the crud on the siphon walls, giving them a chance to grow and accumulate in siphon top rather than staying in the flowing water and leaving the siphon.

For your system, make sure the siphon tube is reasonable clean. If it is, then the issue is the flow through the siphon is too slow. You will need a bigger pump or if the pump is supplying other devices like a skimmer or reactor, you will need to adjust more flow to the tank.

A third possibility is sudsy water. Is there an unusual amount of foam on the surface of the overflow box that sits in the aquarium?

 

[FRANK48]

I have found two ways bubbles tend to become trapped: flow rate and a dirty siphon.

I think air bubble formation in an overflow system is normal. Water flowing through an obstruction or over an obstruction or just falling into water makes little bubbles. Generally, these little bubbles just pass through the siphon. If the water flow is slow, bubbles can accumulate to form a bigger and bigger bubble which is more likely to leave the stream and come to rest at the top of the siphon.

Another factor that seems to influence big bubble formation is the growth of a biofilm and algae on the inner walls of the siphon. Bubbles may adhere slightly better to the crud on the siphon walls, giving them a chance to grow and accumulate in siphon top rather than staying in the flowing water and leaving the siphon.

For your system, make sure the siphon tube is reasonable clean. If it is, then the issue is the flow through the siphon is too slow. You will need a bigger pump or if the pump is supplying other devices like a skimmer or reactor, you will need to adjust more flow to the tank.

A third possibility is sudsy water. Is there an unusual amount of foam on the surface of the overflow box that sits in the aquarium?

My siphon tube kinda looks like it’s half full like it’s not full

 

[Dan_P]

My siphon tube kinda looks like it’s half full like it’s not full

If it starts out full and becomes half full of air quickly, there could be an air leak.

 

[FRANK48]

If it starts out full and becomes half full of air quickly, there could be an air leak.

What does that mean?

 

[Dan_P]

What does that mean?

If I am not mistaken, your overflow system has a siphon tube and you are suppose to start the siphon by removing all the air from the siphon tube.

Making sense?

 

[FRANK48]

If I am not mistaken, your overflow system has a siphon tube and you are suppose to start the siphon by removing all the air from the siphon tube.

Making sense?

Yes

 

[Dan_P]

Yes

Ok.

When you establish the siphon, all the air is removed from the siphon tube, correct? If it is, how long does it take for the air to accumulate to the point the siphon is half full as you reported seeing?

 

[FRANK48]

Ok.

When you establish the siphon, all the air is removed from the siphon tube, correct? If it is, how long does it take for the air to accumulate to the point the siphon is half full as you reported seeing?

i fixed the problem i think. i just had to up my return pump flow and now the siphon is full and i think the flow is stable

 

[Dan_P]

i fixed the problem i think. i just had to up my return pump flow and now the siphon is full and i think the flow is stable

Excellent!