Backyard Aquaponics
A place to discuss aquaponics

Howzit (that's South African for G'day) All,

I spent the whole weekend digging a hole to stick a tank in, putting up some gum poles and one very lonley tower.

The hole took a long time to dig (two full days and a lot of beer) because it hasn't rained here for a while and the ground is bloody rocky. Got down to about 800 mm and hit solid rock. Had to give up and sink the tank as is. I now have renewed respect for people who are unfortunate enough to earn a living digging things.

After giving up on the hole I sunk gumpoles for the grenhouse frame, draped a bit of shadenet to make me feel like I had a greenhouse and then made up a test tower.

Sunk a short gumpole for the tower to stand on and put a lath immediately (secured to the tops of the greenhouse uprights) above it to brace the tower against. This works quite well as you have a bit of adjustment available with the tower compressed between the lath and the stumpy pole it is perched on. The base of the tower is a 110mm drain pipe union that is a loose fit to the pole.

Finally filled the tower with 19mm building stone and tested the flow rate it could accomodate. It seems to be happiest at about 20 litres per minute so I will be using nylon irrigation taps at the inlet end of every tower so that I can balance the flow.

I will be laying the towers out in a grid formation space approximately 1 metre apart. This should allow me space for around 40 towers. Since they are placed on gumpole verticals, should they prove impractical I'll have a nice stong structure to place growbeds on at exactly the right height for drainage as well as having all the required water feeds above and drainage lines below.

Can't wait for fish. Will be stocking with african catfish, which is known as barbel here and tilapia which answer to bream or kurper in our waters.

Later

Mike

Interesting mevans, keep the updates coming!

Wow, looks great. Sounds like you have decided on your fish, any ideas what type of plants you will be growing?

Big Rock! Looks like you have been busy, nice tower and at least you got some of the tank in the ground. Were you going for gravity feed back to the fishies? How did you make the planting positions in your tower?

Yeah nice tower, hope it all goes well for ya, keep us posted!

A tower is my next project how did you soften the pipes - at this stage I only have a hairdryer at my disposal but I dont know if this will generate enough heat??

Looks fantastic ME - is the bottom end of the totem blocked off or will the water dribble out down the wooden upright as well as the pvc outlet?

Thanks for all the comments.

Daniel: I plan on trying to grow leafy greens including various varieties of basil, coriander, rocket, parsley and lettuce in the towers like the one in the picture. Would also like to try chilis but I reckon they will need to be in towers with fewer grow pockets to avoid clogging with their bigger root systems.

Gotfish: Fortunately I was able to get the tank in deep enough that a 1500mm tower standing on a 400mm pole has about 100mm of head on the tank so it can still gravity feed. I'm a little concerned that the water velocity may be low but if that turns out to be the case I'll reduce the height of the towers and increase the length of the support poles to get a bit more head(not that kind . Made the planting positions by cutting a slit in the pipe and then heating the area immediately above it till the plastic started to sag, then pushed it in with gloved thumbs and held till it coolsed - Thanks to Muzza for the method it works like a bomb.

ponicsmad: I can't be sure but I doubt that a hairdryer will cut it. I needed to use the hotter of the two settings on my heat gun to get reliable results.

EKB: The bottom of the tower consists of a pipe union with an inverted male end stopper. I ground the flange off the end stopper and pushed it into the union where it is a tight fit from the below. The stopper then buts against the internal lip in the union forming the floor of the tower. I then drilled a hole 30mm above the midpoint of the union and tapped it for a 20mm electrical conduit adaptor. Screwed the adaptor in with some pvc glue on the threads and then glued in a short length of 20mm conduit. This forms a flange for 25mm poly pipe that is a tight press fit so it will be easy to remove in the event of blockages. I'll make the same fitting on the 50mm pipe that will be the main drain back to the tank.

I'm doing one tower and running it till I see how it works and if I can improve on the design. Once it's working well I will make up another 10 and get the system cycling. My intention is to have a 'modular' infrastructure that will accomodate horizontal beds or towers without any rework.

Will post more updates as it progresses.

Mike

Just a note on the towers............

I think a few of the first attempts went poorly due to clogging of the gravel.

I think that if you had say 5 or 10 towers all being fed from the one source it would work out better, as you have 5X or 10X the area to catch solids.

Just a thought

Steve

Hi steve,

You wrote:

"I think that if you had say 5 or 10 towers all being fed from the one source it would work out better, as you have 5X or 10X the area to catch solids."

Not sure I follow. The towers, there is space for around 40, would all be fed from the tank via an overhead 25mm poly pipe with a tap above each tower.

Do you mean that I should have a header tank with a distribution manifold feeding the towers by gravity or that I should have more towers than the one in the pic?

Mike

This one

just wanted to make sure you just didn't have one tower being fed by your fish. Clogging would be an issue for you if you did

Cool, thanks for confirmation. Since I only have second hand knowledge and a bunch of untested theories I thought I might thave missed something fundamental.

I plan on hooking up the one tower and running it for a bit so that I can evaluate the system. Once it has settled I can improve the design if required and then make up the additional towers.

In theory (there it is again) I can put in 40 towers but I'm not keen to ramp up to anything near that until I have a cooking clue of what i'm doing :-)

its just that the one tower will be doing all the solids filtration, and becasue it is long and thin VS short and wide, it MIGHT tend to block up if you use only the one

Makes sense. My gut feel is that while I can have 40 towers I will end up with 15 to 20 all fed from the tank.

sounds like a plan keep the pictures comming coarser gravel is probably better for the towers too.