Help Cycling Pond

[turbovr6]

Hello Fellow pond owners, I posted a question in the freshwater section and it was suggested to check in here for some help.....



Not being a newbie to cycling, I have cycled quite a few "normal" sized tanks in my life. Now I am trying to cycle my 600 gallon indoor pond.

I was going to take a shot a cycling with pure ammonia but just could not find any! So I went with fish food and raw shrimp, a method that has always worked for me in the past.

So my pond..... I filled it up, treated with Prime, got the ammonia up to 2.0 and then added Stability in the correct amounts for 8 days...NOTHING! Ammonia stayed at 2.0, never seen nitrites, nitrates would go to 5ppm some days, then back to zero. After 2 weeks or so I took a bunch of gravel, bio media, and sponges from two of my established tanks and placed everything in the wet/dry sump filter. It's been another week and the same exact thing!!! No change!

Does the amount of water usually determine the time to cycle? I know it can take quite some time to cycle but I have been testing every day and it is always the same. Ammonia 2.0, nitrites zero. I am using the API master kit, I know it is good because everything in my other tanks test correct.

Pond specs: 600 gallon, temp 77-78 degrees. 2400GPH pump, 75gal sump.
PH 7.2.

Any advice or suggestions would be greatly appreciated! I have a big fish that needs to start his life in the new pond!!!!