I designed my pond with a bog shelf that I thought would be able to take and filter any run off that gets into the pond. Major flaw of my design was not adding a liner to the bog shelf. I have a permeable retention wall between the bog and pond, and want to keep the water up to the top of the retention wall so the bog stays saturated.

I just refilled the pond after having drained and cleaned it. I lost quite a bit of water overnight. The bog area was probably pretty dry, so that may be part of it. I'm going to refill and see if I can reach a good saturation level, which may improve the problem. It depends on how much the surrounding soil might be leeching form the bog.

But if I still see too much water loss, I probably can't do a redesign until next year. I'm thinking of adding a soaker hose into the bog to add more water as needed. This water will seep into the pond through the permeable wall. This isn't going to matter now, since I don't have any fish, but if I do add some goldfish, should I be adding a water conditioner any time I water the bog? Are there any inline carbon filters I could just add to the hose that could do this that might be a better idea? I'm in Chicago, so they chlorinate the hell out of our water.

Thanks