Made 2 backyard ponds (attached together by pumps and hoses) upper pond always drains Help!!

[Tom Keating]

I created 2 ponds for the first time ever. I have been through the ringer trying to get the upper pond (just slightly elevated 30-40 gallons) to stay filled with water and to get the lower one (bigger 60 to 70 gallons)to stop slowly over flowing. I have changed the pumps and hoses a number of times. I have let the water sit for a couple of days with no pumps running and the water level stayed correct so I also know there are no leaks in either pond.

The upper pond had a smaller pump because it is only pumping the water no more than 3 ft up into a tray that is attached to the lower pond. The original hose for upper pond was 1/2" and the original motor was only 80 to 155 GPM. (Being a cheap skate I thought it would be fine.)

The original lower pond which is bigger I put a 300 to 500 GPH pump in it and a 3/4" hose and understandably it was overflowing the top one.

Bottom line is this. I have bought 2 new 300 to 500 GPH, both with 3/4 inch hoses and placed them in the top one and the bottom one. I did some trouble shooting and when I unattached the bottom hose (which returns it back to the top of small rock hill which then cascades water back into the smaller pond) and replaced the 3/4 inch hose with another 3 foot 3/4" hose and simply return the water 3 feet back to the smaller upper pond they both stay balanced. I ran that for 2-3 hours and they stayed balanced. I thought well I've finally got it. So I reattached the buried 10' hose so the lower water can be pumped back to the top of the cycle (the small rock hill) and still the lower bigger pond was over flowing and the water level in the upper smaller pond was slowly going down to the point the filter / pump were uncovered and sucking air.

I thought maybe the "waterfall tray" that was buried in the top of small rock hill at the beginning of the cycle that the 3/4" hose from the bigger lower pond was attached to was slowing down the progress of the water returning in the upper smaller pond, so I removed that and the 3/4" hose at the top of the rock hill was now flowing directly onto the top piece of slate into the upper smaller pond and still it slowly went down to non-functioning level.

the only thing I can think of is that the 3' 3/4" hose pumping from the upper smaller pond into the lower bigger pond is pumping a much shorter distance than the bigger lower ponds 10' 3/4" hose going from the lower pond back to the top of the rock hill starting the cycle all over again...Please help thanks Tom Keating

 

[mrsclem]

Pictures would help but if I'm understanding your setup, the top pond does not flow directly into the lower one. That's how most 2 pond systems are set up. To move water from one pond to the other and pump it back with a 2nd pump the flows would have to match perfectly.

 

[Meyer Jordan]

Clear as mud!!
If I understand this correctly, you are attempting to balance the volume in two (2) separate ponds at different elevations using variable speed pumps with different lengths of plumbing runs.
Does that sound correct? If it is then your problem is-
1). Getting the flow rates to match exactly.
2) Accomplishing #1 while overcoming the difference in friction loss between a 3 foot run and a 10 foot run of plumbing.
This is very, very difficult to accomplish even if you have a very accurate flow meter to use for determining the actual flow rate as friction loss will change as biofilm grows withing the plumbing.
Why connect the two (2) ponds at all unless there is a visible flow between them like a waterfall or stream? Even in those scenarios you would need only One (1) pump.

 

[Tom Keating]

Pictures would help but if I'm understanding your setup, the top pond does not flow directly into the lower one. That's how most 2 pond systems are set up. To move water from one pond to the other and pump it back with a 2nd pump the flows would have to match perfectly.

thanks so much for taking the time to reply.. Correct, correct there is not enough gravity to have it flow into the lower pond so I have a pump doing the work, It seems at times they are syncronized and at other time, not...

 

[tbendl]

I agree with Meyer. 1 pump, pumping from the lower pond to the upper pond. This setup should then force the upper pond to drain back into the lower pond. The flow rate coming from the upper pond to the lower pond will be determined by the pump size (the GPH).