I let the tank sit for a couple days with water and all the ball valves shut just to make sure all the bulkheads didn't leak. Everything was good there.
I tested out the sump and Ultima today. 1st was the sump. Only had 1 leaking pipe, where the overflow bulkhead connects to the ball valve there was a leak which was due to not enough thread tape. Easy fix that took a minute.
2nd issue is that the silicone in the middle sump baffle didn't hold up under pressure from the water rising in the sump so it blew out the silicone seal... I'll try re-siliconing this piece into place but I'm not sure if it will hold. Here's a picture of the failed baffle. I didn't put silicone on the backside bottom of the baffle and I'm assuming that's why it failed.
2nd thing I tested was the plumbing to the ultima and the backflush drain. This was a used ultima so I knew there would be sludge in the ultima that needed to be drained. This was a perfect way to drain the tank. Took about 15 minutes to drain 3/4th of the tank.
I had 1 leak on this portion, it was the soft hose connection to the backflush outlet on the ultima. It seemed that the hose wasn't thick enough to make a gasketing effect on the barb I attached it to and water started pouring out of this connection as soon as I started the backflush.
My fix was putting an old bulkhead gasket over the soft hose, under the clamp to create a gasket tight seal. This seemed to solve the issue. You can kind of see the black gasket over the hose in this picture below.
This hose then drains over to the shower in the room next to the tank.
There was a lot of sludge in the Ultima, this picture only shows a small portion of the grime that came out of it.
Now that I have the tank mostly empty, I need to put some shims under one side. I thought it was level but once it was full I could see the water level was slightly off at the top.
After shimming, I need to buy some fittings to connect my airstones that will go in the K1 chamber in the sump and then completely drain the sump so I can apply some more silicone to that middle baffle.
After that, I think I'll be ready for a re-fill of filtered water that can start cycling the tank!