External pump without drilling sump?

[Psychographic]

I think you need to read my last post....again. You are looking at this from the exit end with no thought to the the supply side when the pump stops.

Jim

I must be missing something, because this makes no sense at all to me. Does'nt the supply side stop dropping when it reaches the level of the water in the sump? Would'nt you need a "Force" to push it below this level?

I can tell you it does work, as I said I have done it on a tank that is still using this method and it has been running for at least 3 years now with not hving to be reprimed.

 

[Psychographic]

I just tested this with clear vinyl tubing. I filled a bucket about 2 foot above one of my tanks made the same loop as shown in the pic with the vinyl tubing, started a syphon and let it run until it lost syphon. The water stopped at the level in the tank and stayed in the tube just as I explained originally.

 

[Jim Tansey]

I'm confused and going to bed, we know it will stop at the water level, the question is does the water stay in the U-tube.

Good Night,

Jim

 

[wrassefan]

The only addition I would add is to add a true union ball valve right in front of the pump for maintenance

I have unions in both the return and feed at the pump....not quite in front but not far for maintenance

 

[wrassefan]

A couple of ball valves would be nice right close too, less mess when maintenance time comes around.

shutoffs are further up not in the pick but part of the system

 

[stevenp]

I'm confused and going to bed, we know it will stop at the water level, the question is does the water stay in the U-tube.

Good Night,

Jim

In my experiment it did. Sounds like it did in the original posters experiment as well.

 

[steve214989]

Wow. Turned into a hot topic. Now I just need to find a pump. lol

 

[Jim Tansey]

Under static or near static conditions the water will stay in the U-tube, the real question is will it clear or partially clear as the water/air backflowes from the aquarium when the pump stops. If it clears the pump will not restart, if it does not your ok, if it partially clears you may or may not have a problem. I would opt to drill 100%, though I can see systems plumbed like this and never having a problem.

Jim

 

[NateHanson]

I just simulated this with a bucket of water and a hose and this is what happened. The water stayed in the upper "U" portion, even with the elevated end open.

Exactly. The water will only drop to the level of the water in the sump. Thus no water drains from the U tube. The U-tube has both lower ends under water, so no air can get into the top. That's assuming that the water falling back to the blue water line in the return line doesn't have so much speed and momentum that it continues far enough to fill the u-tube with air. I think the pump would slow the flow enough to prevent that.

Regardless of all this, I definitely agree with Jim that drilling is the way to go.

 

[JohnK]

Under static or near static conditions the water will stay in the U-tube, the real question is will it clear or partially clear as the water/air backflowes from the aquarium when the pump stops. If it clears the pump will not restart, if it does not your ok, if it partially clears you may or may not have a problem. I would opt to drill 100%, though I can see systems plumbed like this and never having a problem.

Jim

In my previous post I didn't touch on the issue of air being mixed in as the siphion breaks at the tank, but it is a very important thing to consider. (Jim covers it here well.) I also agree about drilling, much better option if it is an option...

 

[Psychographic]

Not trying to be a wiseguy here, if the OP does'nt understand how this works, I would'nt suggest going this route. This pretty much is my philosophy with most any vital part of your system. The reason I say this, should you ever have a problem with it, you need to know how to remedy the situation. Otherwise you have a chance of being "Up the creek without a paddle."

I would do the polarized lens trick, if you are safe, it woud be foolish not to drill the tank.