We’ve made some major progress on the Aquaponics in the last couple of weeks, and now I’m getting ready to start ‘cycling’ the system. This is what you need to do to build up the colonies of beneficial bacteria in the growbeds that will clean the water once we have added the fish. To minimise the risk to the fish you do this cycling ‘fishless’, by adding ammonia manually to the water. Once the bacteria are going well they will feed off this ammonia, turning it into nitrates for the plants. Without the bacteria, ammonia in the fish water would quickly reach a fatal level, so we need to have the bacteria well established before we add any fish.

We’re going to start cycling the completed side of the aquaponics system while I complete the plumbing and gravel-washing on the other sections, and here is the completed side:

Now you can see the plumbing all connected it hopefully makes more sense: The water overflows from the fish tank at the back into the dark grey pipes which feed each growbed. The water then slowly drains through holes in the bottom of the growbeds into the white return pipe, which returns it to the sump.

I’ve connected up the pump too. It’s quite an impressive beast:

What’s even more impressive is the flow from it – the pipe in the photo is 38mm (1.5″):

So now I just have to get the bacteria to build up and we’ll be ready for the fish – I might even start to plant some seeds in the beds while we’re waiting.