Pondless Waterfall pumping issues
We had a pondless waterfall professionally installed 3 years ago, and it has worked great. This year I did the clean out of the rocks myself as the installer never showed up. Ran fine for a couple weeks, and then it started "gurgling" and the amount of water recirculating greatly slowed. The water was "pooling" over the gravel in the basin. We added more water but it just pools.
We pulled out a lot of the gravel, opened the box over the pump, there was a bunch of sludge in the bottom. I scooped that all out, power washed off all the rocks onto a piece of screening, and washed off the pump. For several days it seemed to still be an issue, we left the stones out, my husband worked on it, and it started working perfectly again.
Now we are back in the same situation after less than a month. I have the unit turned off now as we don't want to burn the pump out. Water is just pooling, and won't drain into the gravel to refill the pump box. (these terms may be incorrect, I apologize) When the pump is turned off a while and the water filters back down through the gravel, and then you turn the pump back on, it turns on beautifully and strong, runs for a very short time, then the water is pooling again and the force becomes a trickle.
I have all the pictures I took when the waterfall was installed as well as when we unloaded the stones and had the top off the pump to clean it, if it would help. No call back from our installer guy, he must be doing something else now.
Please let me know if I could provide better information and what it would be. Thanks in advance for any advice.