hang on oveflow?
- Thread starter herpsandreefs
- Start date
Hi Chris,
Water is siphoned down in external overflows. There is a difference in pressure (caused by gravity) between the tank water and the water below it. Water will thus want to move down and there is just enough pressure gradient to "pull" water over the ledge on down.
You need to get a siphon started before it works. That means you need to fill the siphon tube up with water before it will start siphoning (it won't draw water in on its own). There isn't remotely close to enough energy to start the siphon effect on its own.
Hope that helps.
Water is siphoned down in external overflows. There is a difference in pressure (caused by gravity) between the tank water and the water below it. Water will thus want to move down and there is just enough pressure gradient to "pull" water over the ledge on down.
You need to get a siphon started before it works. That means you need to fill the siphon tube up with water before it will start siphoning (it won't draw water in on its own). There isn't remotely close to enough energy to start the siphon effect on its own.
Hope that helps.
Well, in the case of U-tube siphons, when the power fails and the water level in the main tank drops, the 2 levels of water in the overflow equilibrate -- in other words, the siphon siphons till it can siphon no more. The pressure equalizes. The siphon, however, will remain fill with water as long as water is present on both sides to cover the ends of the tube. thus when power on and levels of water begin to rise again, the pressure equilibrium is broken -- restarting the siphon.
In the case of other types -- for instance, CPR overflows, their siphon relies on a pump to maintain siphon and keep water out of the tube. You're in trouble if it gets clogged or blocked by some nefarious necerious snail. Also, when power fails, the pump turns off and siphon is broken quite often!
Unfortunately in both of those latter cases, this can lead to spillage ( :evil: ) if there is too much water present.
U-tube good.
John
In the case of other types -- for instance, CPR overflows, their siphon relies on a pump to maintain siphon and keep water out of the tube. You're in trouble if it gets clogged or blocked by some nefarious necerious snail. Also, when power fails, the pump turns off and siphon is broken quite often!
Unfortunately in both of those latter cases, this can lead to spillage ( :evil: ) if there is too much water present.
U-tube good.
John
I have one as well, and haven't had it fail. Just make sure that you get no air bubbles in the tube. This can happen when the water splashes over into the overflow, and if your flow isn't fast enough, they tend to collect on the "bottom" of the U (which is actually the top because the U is more like an "n" 
).
Some people say to make sure that nothing can get into the flow container as well, like a snail. This could be a major problem, especially if your sump pump exceeds the siphon speed. 8O On mine I've covered the top so that nothing larger than the holes that allow water in can get through.
Oh.. you may be interested in how I start my siphon. Pretty cool. I take a really small airhose and feed it back into the large U. Then, when both ends are submerged, suck out the air with your mouth.. make sure your airhose is long enough, and the siphon should begin it's movement.
~wings~
).Some people say to make sure that nothing can get into the flow container as well, like a snail. This could be a major problem, especially if your sump pump exceeds the siphon speed. 8O On mine I've covered the top so that nothing larger than the holes that allow water in can get through.
Oh.. you may be interested in how I start my siphon. Pretty cool. I take a really small airhose and feed it back into the large U. Then, when both ends are submerged, suck out the air with your mouth.. make sure your airhose is long enough, and the siphon should begin it's movement.
~wings~
don't do it. i had one tube of an overflow like that fail. water level in the tank rose and spilled over.
dripped on to a sterlizer power brick under the tank and started an electrical fire. luckily a friend was there watching the house or i would have lost everything.
here's what i did. sold the damn sump and everything that went with it.
got an Eheim 2229(with wave action) and filled it with live rock fragments and nothing else.
sold the sump skimmer and got a Remora Aqua-C Pro HOT skimmer. best in the biz IMHO.
also got two power heads for water flow. don't get the one's that wave back and forth, they only work a couple months or so.
after i switched to that setup, all my extraneous algae(some of it hair) disappeared. coraline algae started to grow.
fish are healthier, water is pristine. i even have some baby Astrea snails growing. little worms are forming too.
i'll never go back to a sump as long as i live. if you want to keep your sump, drill the tank and set up the sump as a refugium. otherwise, go in the direction i did.
you'll never look back.
dripped on to a sterlizer power brick under the tank and started an electrical fire. luckily a friend was there watching the house or i would have lost everything.
here's what i did. sold the damn sump and everything that went with it.
got an Eheim 2229(with wave action) and filled it with live rock fragments and nothing else.
sold the sump skimmer and got a Remora Aqua-C Pro HOT skimmer. best in the biz IMHO.
also got two power heads for water flow. don't get the one's that wave back and forth, they only work a couple months or so.
after i switched to that setup, all my extraneous algae(some of it hair) disappeared. coraline algae started to grow.
fish are healthier, water is pristine. i even have some baby Astrea snails growing. little worms are forming too.
i'll never go back to a sump as long as i live. if you want to keep your sump, drill the tank and set up the sump as a refugium. otherwise, go in the direction i did.
you'll never look back.
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