Hello everyone. I am a new pond owner ( or maybe it owns me...not sure lol) I am an RN (medically retired) Originally from Florida. Our pond is about 2200 gal ( hope fully will be altered on one low side to hold a bit more) it is about 3.5 ft deep and somewhat kidney shaped. We have a Pond builder 3400 gph pump in a large skimmer that feeds a 150 gal stock tank filled with 18 bags (36X24) lava rock with water celery growing over the top as a bio filter. From this tank flows a pretty strong waterfall. I began adding beneficial bacteria since day one and treated water as although we are on a well, it's not a good well, recovers very slowly so, this was trucked in municipal wated.We currently have about 9 lily's (hardy and tropical) doing well when the koi arnt digging them up! We have about 18 koi. About 4 large (6-12") and the rest smaller.I have a bit of "shade" in the water because it gets full sun much of the day. I had about 1/2 a ton of small rock in the bottom....big mistake, limestone no less, which has since been removed by hand ugh! We have had clear water but no more. We have green water I hate...main reason I joined this forum. I want to SEE my fish.....I am so frustrated currently I could scream. I need to learn a lot.