I'm hooked and building my first system

[mcfarm]

Hi all,
Found an aquaponics ad in a gardening mag, bought Murray's dvd and then tracked down most books (including Gary's) I could find on the subject via the internet - still waiting for the UVI text. Read a lot of info on this and other forums and am taking the plunge - in for a penny, in for a pound.

Luckily I live on a farm with good water supply (dams, springs and tanks) and great infrastructure. One of the sheds will be modified to house the system. Oh and located in southern NSW half an hour from the Canberra. Have grown veggies in soil with mixed success (frosts, insects, birds, drought etcetera), but have kept aquarium fish since before I could walk.

Anyway am about to build a largish test AP system media based flood and drain and with the following bits and pieces -
5000 litre squat plastic rainwater FT,
a smaller 1500 litre plastic rainwater fingerling/quarantine tank,
12x500 litre grow beds (media filled),
a 1000 litre sump (buried IBC),
one 9000 litre submersible pump in the main FT,
a 12,000 litre sump pump,
air stones in the FT's with battery backup.
All housed in a poly carb lean-to on the side of the machinery shed where there is power and water (gravity fed from dam).

The FTs will be slightly out of level/plumb and I hope just enough to get the detritus to flow to the bottom side outlet then to the mechanical strainers/filters. Probably won't work 100% but.........

Trying something a bit different with the GBs in using 500 litre non potable water tanks ($79 from Bunnings '05' polypropylene complete with lids and taps). The reason they are 'non potable' is the lower density of the plastic (food grade for single use only) and hence non reusable food grade - not the plastic itself. These tubs are 1m round tapering slightly to the bottom, and 900 high so no stands required. Plan to fill the bottom 2/3's with washed blue metal (basalt?) drainage gravel (washed in our dam water) and last 1/3 (300mm) with expanded clay. The auto siphons will not be the bell type as they need to go through the wall of the GBs cause the base is on the ground. As I have most of the other stuff the main expense is in the GBs, gravel and autosiphons.

I plan to filter the water as it leaves and re enters the FTs. Taking 70% the top off the rainwater FTs and leaving the 300mm ss mesh filter in place, the water coming in will go through the ss mesh below which will be a woolies green shopping bag. At 99 cents these would have to be the cheapest non woven polypropylene filters around - and they're washable too. Haven't figured out how to use the woolies bags as the water leaves the FT's, but something will occur to me after a glass or two of red.

Why am I going to bother filtering the water? My experience with fish tanks and undergravel filters tells me that eventually the grow beds will clog up with anaerobic gunge - particularly ones that are nearly a metre deep. Worst case I have a two inch 185 micron disc irrigation filter lying around and will press that into service with some sort of coarser pre filter.

Why media based GBs? Corn. I love corn but it's a nutrient hungry plant in soil and I haven't seen it grown in rafts. Hopefully the corn won't fall over in the expanded clay when it's in a greenhouse. Mind you harvesting the ears when the plant starts 1 metre above ground level will be interesting - will need every bit of the 3.3m greenhouse height. Will probably expand the system and add raft beds at some stage for the leafy greens

I've also acquired a solar roof mounted swimming pool heater. Haven't figured out how to incorporate it yet, but winter is months away and I could always do trout.

Fish species? I have silver perch in the farm dams, so will probably stick with them. If I get too many (I wish) they can always be released into one of the dams. There's a hatchery at Wagga, and it's only a 4 hour drive away. Might try trout in winter if I can't get the solar heater working and the trout hatchery is only 2 hours away- we shall see.

Anyway great forum, full of good info, much appreciated thanks. I am a Luddite, but will attempt to post photos in early Feb when I start the construction process to suck it and see. Sorry for the long winded first post too.
Cheers.

[aussieap]

Hi mc. One thing, run ur quarantine system as a separate system. You prolly know this. You can then run whatever salt levels u need to without it impacting ur main system. You could use one of ur gbs as an aquarium plant producer with this set up.
I have found those Bunnings tubs pretty brittle. Careful when drilling for ur gb plumbing.
Is ur shed floor flat? If so, stick ur pump in the middle of the fish tank, fish poo will accumulate their,(spot of least pressure in tank.)
Look fwd to seeing how things go.

[duggeeeea]

Hi Mcfarm
"Trying something a bit different with the GBs in using 500 litre non potable water tanks ($79 from Bunnings '05' polypropylene complete with lids and taps). "
Would you mind giving details of what "area" of Bunnings you bought these (gardening?)? maybe what store? any codes on them? as I drew blanks in Bunnings Darwin.
cheers
Doug

[mcfarm]

Thanks aussieap, hadn't noticed the brittleness of these tanks, but I'll be careful. Will definitely run a small quarantine tank and system separate from the main system. The shed floor is slightly off level (20mm over 3.6 metres) and am now planning to run eel tailed catfish on the bottom (thems good eating) so they will stir things up a bit, probably means I'll use a small continuous run pump that will simply recirculate water in the tank via a shopping bag filter. Will only need to be small and next to no head, should aerate a bit too - might even use an air lift to do the job.

Had a brain wave about the auto siphons for these GBs. They don't need to be inside the grow beds at all. Because these beds sit on the ground/floor the exit point will be through the wall, so why not use the bottom bung hole as draw point and run the auto siphon externally. This means easy adjustment/cleaning, no intrusions into the grow bed surface, the draw point at 850mm down is too low for most roots to foul - but a cage over the hole would keep things clear. Whadyareckon? No drilling holes for roots to foul, no PVC pipe within a pipe within a pipe to stuff around with. Give me a few days and I'll build one and see if it goes. If it works, it won't get any simpler to build.

duggeeeea, the item number on the Bunnings docket is 8015527055732 Tank - Rainwater 500L Green $79.00. The Bunnings in Canberra had a heap of them on a pallet and they come with a lid and a 19mm plastic tap - check out "special orders" if they are not in the rainwater/plumbing area. I asked how much if I bought 10 and the price only came down $3 per tank. They reckon they are a loss leader and cost them $71. Whatever, it's a lot of volume/GB for the money.

Cheers, MC