Check valves? - Tropical Fish Keeping - Aquarium fish care and resources
 3Likes
Reply
 
LinkBack Thread Tools
post #1 of 15 Old 05-06-2013, 08:56 PM Thread Starter
Check valves?

I have my airpump below the water level and unplug it constantly, and it stays off most of the time. The water does siphon out but only up to the water level (the water rises if I push more of the tube underwater and vice versa). Do I need a check valve?
fish keeper 2013 is offline  
Sponsored Links
Advertisement
 
post #2 of 15 Old 05-06-2013, 11:33 PM
Fish keeper,

I would say yes you need a check valve. They are cheap and can save you from a electrical fire. If water is siphoning back into the tube it could eventually lead back into the pump and one day you'll plug it in and "BAM" an electrical fire and you could get hurt. Save yourself the stress and insure your home and family with a 2 - 3 dollar check valve. Be safe.
willow likes this.

-------------* Semper Fortis *-------------
OSagent23 is offline  
post #3 of 15 Old 05-07-2013, 06:22 AM
JDM
Member
 
JDM's Avatar
 
If the hose goes up over the edge of the tank and then down to the stone/bubbler then the water cannot go higher than the waterline without some suction to draw it up and it would have to draw it over the highest point of the hose for it to flow down to the pump. It is quite normal for the water in the hose to rise to the level that you mention.

Checkvalve if you want, not needed though.

Jeff.


Total years fish keeping experience: 7 months, can't start counting in years for a while yet.

The shotgun approach to a planted tank with an LED fixture

Small scale nitrogen cycle with a jar, water and fish food; no substrate, filter etc
JDM is offline  
post #4 of 15 Old 05-07-2013, 06:24 AM Thread Starter
Oh the air pump isn't even connected right now, I have been planning to use it for something else for a while, and I'll make sure the air pump is above the water. I was more thinking for future reference, thanks, I'll get it next time I need it. For now I'll make sure the end of the tube is above the water line so it doesn't flood everywhere.

Do you know why the siphon water in the tube always seems to want to match the water level?
fish keeper 2013 is offline  
post #5 of 15 Old 05-07-2013, 07:37 AM
JDM
Member
 
JDM's Avatar
 
Quote:
Originally Posted by fish keeper 2013 View Post
Oh the air pump isn't even connected right now, I have been planning to use it for something else for a while, and I'll make sure the air pump is above the water. I was more thinking for future reference, thanks, I'll get it next time I need it. For now I'll make sure the end of the tube is above the water line so it doesn't flood everywhere.

Do you know why the siphon water in the tube always seems to want to match the water level?
The same reason that water in a glass is always level. if allowed to flow freely water will always flow to equalize the level throughout the volume even if it is connected by a hose. If you take a long siphon hose and fill it with water and raise the end of the hose, no matter how long it is or how large or small the diameter, the level of the water will always be the same level as the tank level.

Great tool if you are building a deck and don't have a long level to get the support posts all to the same height.

Jeff.


Total years fish keeping experience: 7 months, can't start counting in years for a while yet.

The shotgun approach to a planted tank with an LED fixture

Small scale nitrogen cycle with a jar, water and fish food; no substrate, filter etc
JDM is offline  
post #6 of 15 Old 05-07-2013, 02:19 PM Thread Starter
Quote:
Originally Posted by JDM View Post
The same reason that water in a glass is always level. if allowed to flow freely water will always flow to equalize the level throughout the volume even if it is connected by a hose. If you take a long siphon hose and fill it with water and raise the end of the hose, no matter how long it is or how large or small the diameter, the level of the water will always be the same level as the tank level.

Great tool if you are building a deck and don't have a long level to get the support posts all to the same height.

Jeff.
Then why do we need check valves if water always strives to equilize?
fish keeper 2013 is offline  
post #7 of 15 Old 05-07-2013, 02:22 PM
JDM
Member
 
JDM's Avatar
 
Quote:
Originally Posted by fish keeper 2013 View Post
Then why do we need check valves if water always strives to equilize?
You don't unless the water actually goes over the side of the tank in the hose to a canister filter perhaps... but even then just a shut off is fine to keep the water in the hose while the canister is disconnected.

If everyone uses them, maybe it's just in case they accidentally suck on the air hose which would be a water problem... but I can't see that happening.

Do air pumps reverse sometimes?

Jeff.


Total years fish keeping experience: 7 months, can't start counting in years for a while yet.

The shotgun approach to a planted tank with an LED fixture

Small scale nitrogen cycle with a jar, water and fish food; no substrate, filter etc
JDM is offline  
post #8 of 15 Old 05-07-2013, 02:31 PM
Member
 
MoneyMitch's Avatar
 
goes to show you don't need them in a diy co2 setup either - don't know why people use them unless their setup is not air tight which then negates the whole diy co2 in the first place.
MoneyMitch is offline  
post #9 of 15 Old 05-07-2013, 02:46 PM
Quote:
Originally Posted by fish keeper 2013 View Post
I have my airpump below the water level and unplug it constantly, and it stays off most of the time. The water does siphon out but only up to the water level (the water rises if I push more of the tube underwater and vice versa). Do I need a check valve?

My answer to needing a check valve for the air pump below the waterline that is unplugged constantly is accurate. You dont need a cehck valve for a DIY CO2 system or for an airpump that is above the water line because in a DIY CO2 system there are no electrics and the system is usually sealed tight. In a pump that is above the water line the water will not rise up into the pump. Gravity and equilibruim is at work here.

I dont see why you wouldnt use a check valve in any case though for a pump either below or above the water line. Its safe, it cost 2 maybe 3 dollars and what happens if someone/something knocks the pump onto the floor when its not plugged in? A simple 2 maybe 3 dollar tool can save you hundereds of dollars. Its safety verses possibilities.

-------------* Semper Fortis *-------------
OSagent23 is offline  
post #10 of 15 Old 05-07-2013, 03:13 PM
For what it's worth every pump I've ever bought comes with a check valve and a manufacturers recommendation to use it if the pump will sit below the water line.
Although starting a siphon may be unlikely, it's just a precaution against potential damage or shock. Much like using a GFIC (ground fault interrupter circuit) for lights, heaters and such.
I think they sell them at wallymart in two packs for a couple of dollars.
jentralala likes this.

Father Knows Best but Abbey knows everything! I once knew everything, then I asked one question.
` ...><((((>` . . ` . . . ><((((> . ` .. . ><((((>
AbbeysDad is offline  
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome