Backyard Aquaponics
A place to discuss aquaponics

8 years ago we bought the house adjacent to us and promptly demolished it. The land has a 2250 lt concrete septic tank 2m h x 1.25 in dia. Yesterday i removed the concrete top and syphoned off the water. We have two huge fig trees very close to the tank. There roots had grown in the outlet hole and down into the tank. The bottom 150mm of the tank was a solid matt of fine tree roots. I cut it up into 300mm cubes and took it to our local dump. There were no solids what so ever in the tank. The water was crystal clear and the tree roots must have used any available matter as nutrient for growth. Today im going to pick up an orange sp100 pump very similar to the ebara optima. Whilst droping the shit off at the dump i picked up a 50m roll of unused 32mm ag pipe for $2. But wait theres more a stainless stell tub for a gb $2. I have a few questions for the aquaponicians............
1, what is the best way to disinfect the tank. I was thinking a massive dose of pool chlorine or maybe salt. After scrubbing etc. The other metrhod i had thought of was maybe a fire assisted with the garden blower to raise the temp and kill nastys.
2, Is there a problem with leachates the tank is old so ph may not be an issue, i was more concerned with e. coli or similar.
3 Would a bitumen coat or a swimming pool paint circumvent bacteria problems?
4 The tank no longer smeels bad acording to darling partner (i have no sence of smell)
cheers Pete
pics to follow this arvo

hey Pete, good to have you back again. Still in Mt Morgan? A rinse out with some nice acidic Dee River water maybe? then, is the tank in the sun at all? a week or two of sun cooking?

The thing is probably clean now. A bit of sunshine won't hurt. UV light is deadly on almost all bad bugs.

Good luck,
Ron

its in dappled light beneath a tree im going down to scrub it out now. Just bought a load of 12mm agg quarts mix 30 dollars for a bobcat bucket which i thought was resonable. Will probably be enough for three baths. I priced hydrotron but they wanted 45$ 4for 45 lts which i thought was over the top. Purchased a pump but then half way home i n oticed on the box the bearings where in an oil bath so took it back. I contacted monya to get a price on the ebara optima. How is your ebara going Jaime ? Yes im still in mount morgan. Im only about 75 metres from the river. The state and fed govt are doing a massive cleanup taking the first 2 meteres of silt from the river . But since the new fed govt came to power work has stopped.
thanks
pete

fire might not be the best, it would probably weaken the concrete.

would it need dis-infecting after 8 years of non use, no solids and clear water?
i'd be inclined to just let it dry out completely and if you still wanted to do "something" then spray the inner surfaces with strong bleach solution.

This would be more economical than filling it then dosing it. Be aware that it is probably considered a confined space and that the chlorine fumes may get strong. safety first. Damned work safe official peering over my right shoulder. (you think i'm kidding? )

thanks for the reply steve, im inclined to agree with you there seems to be no smell so i might just dry it and bleach it. Still looking for a good pump but.
cheers
pete

yeh, sounds good.

maybe just make up a solution and put it into one of those big mama backpack pesticide sprayers. check the side of the bottle for directions i'd say somewhere around the 1:3 mark

the ebara is doing very well. we never see it, we only see the water returning to the monster, just what you want from a pump

I agree with Steve on the bleach remedy. 10% bleach solution will kill the Parvo virus on surfaces, which is highly contagious and deadly for puppies and unvaccanated dogs. E-coli is a bacteria and much easier to kill. Make sure to rinse extremely well afterwards and allow to dry. Should be good to use after that.

im stuck for a pump. Ive been searching the internet and there is some cheap ones. Im thinking i might get a cheap one and take one for the team. That is try it out and see how long it lasts. I haave some cheapo electrical tools i have been using for years on a daily basis and they are still operating. To day i went to the dump shop in Rockhampton looking for hardware and scored a linear air pump a nitto kohki la60a 60 watt with an 18mm outlet. I pluged it in when i got home and it works perfectly all for $5.00. So i can attach a stone or two and airate my sump. I have three beds filled with agg and readyto go, they are running at $15.00 to fill each bath with the agg. Ill fill the sump tomorrow and start it off with some pond scum from an existing goldfish bath. Even fish are not cheap $1.95 for the cheapest non colour goldy. That is dearer than a native fish. Native Fish pellets were $16.00 a kilo. If any one comes across a pump, or any info on a good pump please pm me .

hey blue your my kind of guy, build from cheap as possible, beat me on the s/s tub I paid $5 for mine but got a 2400lt tank for a carton of TED's, but I did post in your pump thread on what I did and I ended up with an excellent pump, twice as big as what I need but planned for expansion, draws only 90 watts and running 24/7 about $17 per month to run

put another two bath growbeds in today and three stainless tubs for growbeds. I have mounted everything on old trampoline frames i got from the dump. They fit three baths to a frame and i just run recycled 3 x 2 hardwood across the top to support the bath.
I increased the size of the syphon surround pipe from 100 to 150 as i had difficulty getting my hand down the inside. I am working as a plumber at the moment so all pipe is offcuts or secondhand or found. Today i experimented with running the syphon pipe out of the bath using ZERO fittings. I want to reduce the ampount of fittings i use on my whole system. Even though i get them at trade price they all mount up so that in the end you spend hundreds on fittings. So here is what i did ill post a pic soon of the through bath fitting. I got a hole saw and drilled a 100 mm hole through an old toilet cistern. I wound up with a 3mm x 100mm plastic disc. Through the middle of which i drilled a 32mm hole to take my poly syphon pipe. I had to tweak the hole by scraping it with a stanley knife. I slash cut the end of the poly pipe and pushed it through the hole in the centre of the disk. I was a really tight fit. Then i simply use metal thread tex screws to attach the disk to the bath. I put silicon under the disk before fitting. I filled the bath and i only got one small leak around the centre pipe, just a drip. It would track down the poly pipe to the 90mm return anyway so no fuss. Zero fittings except 4 screws. I have to tweak the syphons a bit. Following my zero fitting dream i placed a 50mm dwv over the syphon riser or standpipe. To mean to buy an end cap i bored anothe hole and made a 50mm disc and siliconed it in the pipe. It worked i got the syphon working but it is slow. Ill have to reread lkb's thread on autosyphons again.
I hooked up yesterdays find the nitto air compressor in the foreground of the pic of the sump.
here are the pics.

more pics

how do i load more than one pic?

Just like that Bluefin

And you've made the bathtub brigade really happy.... good stuff mate.