I do not want those plants to compete with the humus availability in the aquaponics setup.
In aquaponics, you cannot simply dump loads of humus because it messes with the water chemistry of the fish - that is done in hydroponics. Fish eat biomass which bacteria break down eventually into humus among other things. This is very generalized but they have classes in this and the field of study is called soil science. I am no expert or claim to be because this is really complicated stuff, I just brushed up on the basics
H Ludi Tyler wrote:
A lot of people put in the plants before they add fish, providing nutrients for the plants with pee-ponics or compost tea, etc.
Fred, setting up an aquaponics system is not something most people can just walk into. Because it occurs naturally does in no way shape or form mean it is simple. I could be wrong though, you could be one of those few people who have actually set up a system with initial success. If you are one of those please upload some pictures and share with us your details. With this said, I know Ludi is getting some experience with a system of her own and it is difficult initially.
Another note, you are confusing solid waist (humin) with water soluble humus. But you are correct in that I could have worded myself more efficiently in explaining the chemistry of the water when adding an arbitrary amount of humus and other nutrients. So with this said, in hydroponic systems, the water chemistry is not designed to accommodate fish as nutrients are provided - I do not want to go into details on this because it is lengthy to explain.
Neal McSpadden wrote:
What? If you are doing one of the standard designs (tried thousands of times), it's relatively foolproof.
The simplest design is to have:
grow bed volume = fish tank volume
grow bed filled with hydroton or river-rock gravel
no more than 1 lb of fish (adult size) per gallon of fish tank
pump turns on and off once an hour, and pumps at least the whole volume of the fish tank in that one cycle
grow bed drains back to fish tank with a stand-pipe
During the spring or summer fill the system, put in a few goldfish to kick the system into gear, wait a month (feeding fish along the way), add more fish and plants.
Obviously there are infinite variations to this, and you can completely geek out on NH4/NO2/NO3/DO/TDS levels. But the basics totally work.
I was wondering the same thing about the solids which would eventually accumulate in the fish tank and in the grow beds. Some people have established worms in the growbeds but that doesn't seem to address the fish tank. Also, I have read that even so eventually you have to clean or replace the medium in the grow beds.
What I am looking at (as well as worms in the beds) is having a sloped v shaped drain on the bottom of the tank which can be drained from time to time into a biomass system to produce methane..(other stuff could be added to the fish tank slurry in the digester). Any experience or opinions on this? I am planning on a pretty big system..about 1200 gallons, so what to do about this stuff is something I want to have a handle on before getting into it too far.