Backyard Aquaponics
A place to discuss aquaponics

Bird netting, coke bottle lids etc, plastic pallet strapping

I have flooded tubes too, I try to keep the water level as high as possible so the roots when they are small can reach the water. I never bother lowering the level though when the plants grow as I don't see the point and also I often have plants of varying sizes planted in the tubes so it would make it difficult. Keeping the water level high all the time also makes it more thermally stable I would think and keeps the roots in more water not just at the bottom of the pipe where particles can build up. I have had towers, flooded tubes and media GBs and the flooded pipes have been the most successful so far.. In fact I am pulling my 10 strawberry towers and replacing with more flooded tubes for that reason.

Thanks all for the comments & suggestions


Ive got some old prawn mesh & guess Ill just have to slowly add the rest of the filter material as I find it.

Ive read a few more post here & have already come up with improvements I can make to my system Im looking forward to seeing growth rates & making changes when I get home in a month.

Looks great, Graham.

Just thought Id show the way my water returns from the growbed through the bell syphon in to my IBC system. I think it allows more DO to be transferred into the FT water ?
[youtube]http://youtu.be/HHGvwBXVfh4[/youtube]

when embeding a youtube video - just copy the last number/letters 'HHGvwBXVfh4'

like this


resulting in this




**EDIT - just watched it - freakin fantastic!!! wow how did you make it do that? loose standpipe?

That is awesome!

Could probably use a barrel union to make that happen as well...cool

Im shore side again so time for an update.
Thanks Jayendra I just couldn't work that one out, it was the first time I have used Youtube also ! You nailed it with the loose stand pipe. It just started as a way to adjust the water height in the GB. A simple collar is made out of the same pipe the stand pipe is made from, this is put over the stand pipe & thread tape is wrapped around the bottom of the collar. Once the correct water level is found in the GB the collar is glued in place & more thread tape is wrapped around to make a good seal. After a long period the syphon may struggle to spin, simply remove & apply more tape.

The NFT system is going well. Reusing old clay pebbles has helped things along as they already had the bacteria & some nutrients on them. Some of the salad greens have sprouted & we are thinning these out till there is only 2 plants per cup.


I plan on harvesting a few fish ( silver perch ) out of another IBC so I can move it & add it to the main system, it been running for 18 months so will be interesting to see the results.
Will post some photos

Ok harvested the 4 of biggest Perch & transferred the rest to another tank. They all looked very healthy. The kids said they tasted great & had great fun catching them.

From R-L they were 441g-32cm, 375g-31.5cm, 330g-30cm, 280g-27.5cm
Is this average size/growth for 18 months for silver perch ?

Ive had some success with rafts in the past. This photo was of a Celery that got attacked by bugs in summer, I treated the bugs with home made white oil spray & left it in the raft a bit too long & now the roots are growing through the foam raft.
What is the consensus of opinion with trimming roots on plants in raft & nft systems ?
Here's another raft was taken over by the plants, this time by mint cuttings again left too long in a bath tub pond. I know mint is very evasive & unfortunately the raft broke up trying to get the pots out, bummer !
Any suggestions with what to do with excess mint ?

Catch Ya
GTK

Trim them up.

Gday All
A bit of an update on my system. I've placed the last IBC in line with the rest of the system & draining back to the FT, all the water levels are remaining stable.
I estimate the total water volume to be ~ 4500 L
with GB volume ~ 1200 L
+ Bio/RFF filter, NFT with 90/70mm pots

This will be the last of the expansion for now until the fish bio mass increase enough to require more filtration.
The Silver perch have slowed feeding as the water temps have dropped & the Nitrates have dropped accordingly.

The water readings today are : PH 8
ammonia 0.25
nitrite 0
nitrate 10
The PH has always been high due to my water source being the well water with a PH 8.2 I've read here that the PH will slowly drop as the AP system matures. It hasn't done much in this system over the last 18 months never dropping below PH 7.8 {average PH 8}
The plants are all growing well but I have never had any luck with strawberries, the leaves just start turning brown from the edge until they just rot off @ the stem[Punnets came from Bunning's ]. I've read that strawbs like a slightly acid soil, I guess its the same for AP ? My kids love them so would like to grow them well. Is an PH adjustment required ( I would prefer not to add acid ) What other plants require lower PH ?

The system has timers on all the pumps ( the NFT is running 24-7 ). A 12v 70L/H Boyu air pump supplies air to all the tanks, its very noisy & maybe under powered for the job ( will make this into the back up air ) & get a 240v air pump. Any suggestions for reliable & quiet air pump ?
Thanks in advance

GTK

Your pH may eventually come down. It really just depends on if enough acid is being produced by the system to offset the buffering provided in your water. Since you're adding more buffer each time you top the system up it's difficult to say but for most people the pH does eventually go down. It took two years for this to happen in my system but it did eventually (it was the same pH as your system). Higher fish loads would mean more feeding and more acid production but of course this comes with having to watch the system more closely and the need for enough grow beds or filtration to process the solids. Other than this, you are left with the addition of acid . Hope this makes sense. I can give you some information on adding acid if you'd like (FYI - If you decide to do this on your own, it's best to adjust by adding to your top up water, not directly to your system)

You probably already know this but watch your ammonia levels and look at the pH and temp to see if you're getting into the toxic range. I forgot to look and see where in the world you are so I don't know if it's Winter or Summer for you. The High pH you're running makes the ammonia more likely to be toxic. There is a graph to help determine this in the IBC's of Aquaponics (there's a link at the top of the page)

Strawberries are a difficult crop to grow in AP. Most people have troubles because Strawberries are sensitive to salt and for one reason or another they have to salt their system water. If having salt in the system isn't the issue then it might be the pH (seems likely) but I'm not sure

Can't help you with the air pump.

Cheers

Thanks Scotty
The relationship Ammonia/PH/Temp has always been in the back of my mind Re: toxic levels. So I have always erred on the side of caution, having plenty of redundancy in the system. Its winter here in Western Australia so the temps are low { Tank water 16*c } so its not so much of a risk at the moment. There is still more room to increase filtration as the flow in the NFT is only 2000L/H.
Well I think the Strawbs can be left in the ground its just they are more susceptible to insect attack in the dirt. nature can run its course in the AP. I'll try using rain water for top ups while there's some around, we don't get much rain here in the mid west of Western Australia so this is not an option in summer.
Will keep monitoring the ammonia levels as the water temps increase as I've read that NFT tubes heat up the water temps quickly in the summer months. Hope to have more fingerlings & possibly more GB area by then.
Appreciate your input.
Regards
GTK

Found this guy in a bunch of celery & also found tadpoles in bathtub today, its so nice to have the locals thriving in the back yard. Have always have had a water source around the house over the last 15 years, so they have always been able to breed so seem to find them randomly in the garden. Mrs hates them but I think they show a healthy Eco system.

Anyone know what type of frog it is ?


Obviously not endangered & a lot better than cane toads !!