Well, It took me a while to get the greenhouse built and the grow beds built. In the beginning of April, I finally finished the plumbing of my system.
It consists of a 300 Gallon fish tank, a 150 Gallon sump tank, a 3X6 and a 3X4 grow bed, a Bio Filter and a Radial Flow filter. I am using Hydroton in my grow beds. I used 1 inch PVC pipe for the plumbing and 1 MAX-FLO 1350 pump. I also built 2 venturi's to see if I could get away with not having an air pump. I thought that the ebb and flow of the grow beds and the added venturi's would provide enough oxygen for the system.
I filled the system with water and ran it a few days. The first thing I noticed was that the venturi's were not sucking air. No matter what I tried, they did not work. The fish tank water was brown and murky even though I washed the hydroton before I put it into the grow beds.
I turned off the system and removed the venturi's. I bought an air pump. I did a 50% water change. I started up the system again and the next day the water was crystal clear. There was some precipitate on the bottom of the fish tank. I vacuumed out the debris with a shop vac.
There was something I did not notice before. The sump tank water level dropped lower than the water pump. I checked the flow rate of my grow beds. they were cycling (flooding and draining) every 15 minutes. I checked the flow of the fish tank to the sump tank. It was 90 gallons an hour. Whenever the grow beds were filling at the same exact time there was a water deficit.
I turned off the system and changed the PVC pipe to a diameter of 2 inches going to the radial flow filter and into the sump tank. The rule is that all of the fish tank water should be cycled at least 1 time an hour. So I need a flow rate of 300 gallons an hour from my fish tank to the sump tank.
I was very excited to start fishless cycling. I have about 500 gallons of water in the system. I was not about to go cap full to cap full of ammonia to get the ammonia level up to 2 PPM. I shut down the system and just worked with the 300 gallon fish tank. I figured that if I added a little too much ammonia, when I turned the system back on and the rest of the water was mixed in, the reading should turn out ok. I mixed in a 1/2 a cup of ammonia and took a reading using the API Test Kit. It showed .25 PPM. OK. I mixed in another 1/2 cup of ammonia. I took another reading. I was called away so the sample was sitting in the rack. When I came back The reading was off the charts! I thought that maybe the system needed to be cycled. I turned the system back on and waited a day. The reading was the same.
What happened??? How could this be??? I read the API instructions again and realized that I did not wait the prescribed time before I took the reading. You need to wait 5 minutes before the reading is valid. I removed 3/4 of the water in my system. I drained the grow beds and filled them with clean water to try and wash out some of the ammonia there. I cycled the system over night. the ammonia reading is 4 PPM. The water temperature of the system is 60 F. I am going to let the system cycle for a few days and check it again.
Life is a learning experience. I have learned a lot. There is a lot more to learn. I hope this blog will help someone else not make the same mistakes I did.