I would like to thank Ranchugirl, Jetman73, and Scott for their input concerning my dilemma. I live in Cape Coral, Florida and apparrently we down here have to import most of our decorative rock from more northern states. Native rocks are ugly.
Scott suggested I not line the bottom of the pond with rocks as disease may occur. If this is the case what should I line the bottom with? Also I'm curious why Jetman suggested 4 foot depth.
I'll go online in search of "fiberglass" rocks...as suggested by Scott... sounds interesting.
New question... I've heard differing opinions about using EPDM rubber roofing liner... some say it will kill the fish... others say there is nothing dangerous about it. 45 mil thickness and durability are important factors, but not if it's gonna kill the fish. What say you?

Thanks all!!

I don't know anything about roof liner? I used the rubber pond liner, the thickest stuff I could find. I did not line the bottom of my pond with anything, just liner. For a koi pond you also want your walls of your pond to be straight down. Yes 4 feet is optimal if you are going to have koi, of course deeper is even better, mine goes down 5 feet at it's deepest. They need the room to grow. If you are going to have just pond comets you really wouldn't need to go so deep.

I can imagine that shipped in rock would be more expensive there. I love the look of river rock and I'd think it wouldn't have to come too far to get to Florida? You might want to check around to see if anyone has it and how much. The fiber glass rocks are usually large, they look real. It's a cool idea, plus you can get fiber glass rock water falls that look real as well. They are quite expensive though.


Remember before you put your liner down you'll want to line the dirt with something, like a few layers of newspaper. I used tarps to line under my liner, this is to help from little rocks surfacing under your liner and damaging it.


Scott

I don't remember if you are doing a koi pond or a watergarden. If you are doing a koi pond the added depth has many benefits too a koi. You can increase the gallonage for the same area, the water will be more stable temp wise, and here is the kicker, the koi will be able too develop correctly. If you keep them in a shallow pond only, there are muscles that the koi will never use and it will be impossible too grow it too its potential.
If you are going too use rocks only use them for the cap or waterfall on a pond. Just like Scott said, NEVER use them in the bottom. That is a recipe for disaster if you ask me.
Buy your liner from a pond store and don't worry about it. Some roofing liners do have additives that are not compatible with fish. Better safe than sorry. Look for an EPDM 45 mil liner if you use one. They are not that expensive and are extremely durable. And before they laid my liner in they surrounded the outside with masonite board. I had no idea at the time but it seemed too work well.
Good luck and if you want a koi pond check out some info about bottom drains.