I am so sorry about the leaks. I can completely imagine how defeated you feel. I had one little area where I thought I had a hole and my heart sunk. I feel sick just imagining what it would be like if our liner seam leaks! I will send good vibes in your direction (and some prayers too) that you get it figured out and that the problem isn't as extensive as you fear.
Do you ever watch Bama Bass on YouTube? Aquascape did a backyard pond for him and that is how I discovered his channel.
He is currently working on an enormous, clay lined pond for fishing - so it is a different situation. But he had a leak and used something to fix it. Since the pond is so huge and not lined, he poured something in the water that flowed into the leak, swelled up and blocked it. I don't know if it could be used in the case of a liner pond, but it might be worth looking into?
watch
Do you ever watch Bama Bass on YouTube? Aquascape did a backyard pond for him and that is how I discovered his channel.
He is currently working on an enormous, clay lined pond for fishing - so it is a different situation. But he had a leak and used something to fix it. Since the pond is so huge and not lined, he poured something in the water that flowed into the leak, swelled up and blocked it. I don't know if it could be used in the case of a liner pond, but it might be worth looking into?
watch