Having played with Aquaponics first hand on and off for two years, I was shocked to discover the constant Flood and Drain system with Hydroton as the media has a starting point that is quite logical and making sense using sand as media and also giving a long cycle of time (2 hours) for water drainage and drying in the sand grow bed. This system was started by Mark McMurtry in 1985.
The major problem with Hydroton (expanded clay balls) based system is that the fish waste is ended up in the bottom of the grow bed making it filthy and needing to place worms to digest the waste. But the waste sits at the very bottom of the grow bed where there is always some water left there. This makes it hard for the worms to stay there. The ideal scenario is for the waste to stay on the top of grow bed, which is exactly what iAVS does.
The other problem with the constant Flood and Drain system is that there is no time for the fish waste to be aerated and digested by the bacterias as the system is always wet. In fact, the plants do not need to be watered all the time, just when needed. Constant Flood and Drain is an overkill. As a contrast, iAVS gives both the fish and plants almost a total of 2 hours of resting (including 10 minute water pumping and 10 minute drainage), plus no need to pump water at night. The last feeding of fish should be no later than 2 pm and then little fish waste will be produced after the pause of water pumping between 6 pm and 6 am.
Once I found out about iAVS and tried the smallest version of it, I now see why it is superior to the current more popular system that everyone is using. While I am in the process of converting to iAVS and testing it further, I post three videos about it in the following. Hope you see all the benefits of iAVS:
Brief introduction to iAVS:
An above ground iAVs setup:
Murray’s iAV Sand Aquaponics System:
You can also learn all the details about iAVS from this website: iavs.info