Bubbles in the tank

[reewik]

Does anyone else suffer from lots of bubbles in their tank. I have a sump and skimmer. i am going to try the sock method and any other method. It just seems to be getting worse. Any ideas?

The last thread was an accident and it will not allow me to delete it?

[fishdoc11]

What kind of skimmer do you have? Is it venturi or air pump driven? If it is a venturi you probably need to clean the valve. You also might try tuning it so the flow through the skimmer is a little less.

[reewik]

Fishdoc11,

It is a venturi.. by tunning you mean lessen the amount of flow? As in a valve to slow down the pump. The valve is pretty new. 5 month old max. It is above water and out of the tank.

[fishdoc11]

There is an inlet where air goes into the water. At this point ( it will be touching the water usually located in or very near the pump ) there is a small opening that needs to be cleaned about once a month or so. You may have to disassemble the skimmer to get to it. This "hole" gets clogged up with calcium precipitate. I use a paper clip to clean mine. You have to be carefull not to damage the opening but also use enough force to "shave away" the calcium. That should fix your problem. If it does'nt, slow down the water flow not the air.

[reewik]

I do not have the opening you suggested. I have a n Excalibur skimmer. This is powered by a powerhead which had a venturi unit on the intake of the power head to make the bubbles. I will try to slow down the flow of the water with a valve if I have one.

[cwa46]

Why don't you just turn off the skimmer and see if the bubbles go away. There are many sources of bubbles. One that casues a lot of problems is pump cavitation. Usually caused by improper pump-pipe-head combinations.

[reewik]

Please explain that one to me. When I turn off the skimmer ,you are right, not all the bubbles go away. Its not like it hurts anything, I would love a bubbleless tank.

[cwa46]

Well since the bubbles aren't from the skimmer, they must be from something else.

Every pump is designed for a pressure range of operation. If your pump is designed for higher pressure than you need, it can out-pump the supply of water coming into the pump. That is to say the pressure drops on the input side to lower than the vapor pressure of water. This forms bubbles of water vapor in the water.

If this is your problem, you can test by putting a valve "AFTER" your pump and turning down the valve. If at some point before fully closing the valve, the bubbles stop then it is being casued by cavitation. There are several ways to fix the problem if it is cavitation. Let me know if it is.

[reewik]

Now I just need to find a valve.

[cwa46]

Its not a bad idea to have a valve on teh return line anyway. Remeber to put the valve on the output side of the pump. If you limit the input, you may burn up the motor.

To experiment, can't you block the flow without a valve. Can you put your finger over the outlet or partially block it to slow down the flow?

[reewik]

Thanks, I will experiment today.

[fishdoc11]

Eric,
Just so you know you will probably want to get a gate valve not a ball valve. They are much easier to adjust. I just assumed you had a valve. That's why I recommended slowing down the flow.

[reewik]

I did I cannot find it. I took it off because I wanted max flow. I will see if I can find it. Thanks man!

[fishdoc11]

Neither of my skimmers work wide open. Both are overdriven by the pumps that came with them. In fact one you have to turn back to about 20%. Good Luck!

[reewik]

Thanks

[cwa46]

I am not talking about skimmer pumps. I am talking about return pumps from the sump to the tank. I don't know about getting bubbles from an overdriven skimmer, but we turned it off already? Maybe I am confused and giving bad advice.

[reewik]

I know what you were referring to. I think I need to do both.

[rcmike]

Speaking of gate valves, has anyone found any around here that are pvc? I have looked for them at several places and can't find any.

[fishdoc11]

Maybe I am confused too. I think were both trying to help with problems weve had individually. Although I think it makes sense to have valves on both. Unfortunately I don't have much experience with sumps as I don't have one on either of my tanks so i apologize if I have further complicated matters.

[cwa46]

Originally posted by rcmike
Speaking of gate valves, has anyone found any around here that are pvc? I have looked for them at several places and can't find any.

Nothing local but on the web try Aquatic Eco-Systems.