Aquaponics - Topup water

Water water everywhere etc...

My aquaponics system needs topup water every few days because the plants use quite a bit, and there is some loss to evaporation.

I would guess I'm adding around three or four litres of water per day on average. That's around a gallon for people in Gallonland.

I'm not really sure how far that amount of water would go in a dirt garden, but on a hot windy day, I'd say you would need that on my two tomato plants alone. Actually, if I was growing my two tomatoes in dirt, as a potplant, I think I'd need twice that much per day.

Much of my water saving might be about the grow house, but because I've never grown in dirt in a growhouse, I cant really offer much of an opinion.

It's often said that an aquaponics system uses around 10% of what you might expect to use in a dirt garden producing the same amount of food.

To combat the deadly toxic effect on fish brought about by the chlorine in my water supply, the water needs to sit for a day or so before being added to the fishy's world.

I choose to be a bit more lazy than that and add it to a large container every few days.

The cover has a small hole to allow water in but generally keep out falling leaves and flowers.

Lately I've been collecting a lot of flowers from a tree in my backyard, and I've also been losing fish. Since the cover went on I haven't had any more deaths, and the fish that were sick are getting better. It's probably just coincidence, but I'm not about to test it by taking off the cover, or adding flowers, so I'll never know.

I guess that's how superstition starts.

I don't leave my water to sit before adding it because I'm lazy and instead, force a delay and dilution on it before the fish get to see too much of it.

I create the delay and dilution by having move from the first container to the second via this thin plastic pipe that I have restricted by tying a loose knot in it. As a result of the knot, it drips at a reasonably steady pace.

You can just see a little clearing of the duckweed near the loop on the left. That clearing is caused by the drips falling at a rate or around a drop every few seconds.

I don't know how much water there is in a drop coming from a knot, so I figure there's not a lot of cause to measure the length of time between them.

From there it flows in and out through a siphon connecting my duckweed tank to the fishtank. The connection between these two tanks means that the depth of one is reflected in the depth of the other. Their depths rise and fall as the grow bed is filled and emptied, but not by as much as the fishtank would rise and fall if it were supplying all the water to the grow bed by itself.

The added water keeps the depth of the fishtank closer to full, and also adds thermal mass to the system just because there is extra water in the growhouse.

This chain from tap to fishtank has grown longer and longer over the months, but the flow does get to the tank in the end.











A further increase in thermal mass will be gained by my adding the big orange container to the inside of my growhouse. It will take up a lot of space, but I can use it to rest the NFT tubes on, and give them a new sense of security. Their current bucket legs are showing signs of getting soft on the hotter days, and I get the feeling I'm only a few days away from a disaster. If the buckets fail, the pipes fall, and the pump just keeps emptying the fishtank into them in a futile attempt to fill the world.

So the plan is, move the orange tank inside and make it the new legs of the NFT pipes. This will involve two people getting into the little growhouse and holding up the NFT pipes, while a third and forth clear out the old legs, and drag in the heavy container of water. That's way too many people in such a small space, and will no doubt end in at least a moderate disaster, but it has to be done.


A lot of my nightmares end in dry fish.


120 things in 20 years is a lot of things. I'm half way through my second year and I'm still sorting out my aquaponic's topup water.