Backyard Aquaponics
A place to discuss aquaponics

Hi all I have just created a vid of construction. I am mostly pleased with the outcome and look forward to adding fish (jade perch) soon. I have been fish less cycling and had my first nitrite reading this morning after about 12 days zero readings!

[url]http://www.youtube.com/watch?v=9VYba1fXLyE/url]

http://www.youtube.com/watch?v=9VYba1fXLyE
Cheers

Welcome to the forum.
Great vid and really nice looking system
What's cracker dust?

What's left over after Christmas....

I Googled, I now know

Cracker or crusher dust is a by product of producing bluestone gravel used to make most of the roads in Australia. Basically its all the little stones that are produced when bigger gravel is crushed.
Its used for all sorts of things. It is very good for making a flat hard base for something like water tanks, pavers, etc because it is easy to smooth out and packs very hard.

And coincidentally exactly what we're discussing in your thread

Love the music to the video, it distracted me as I bopped along to the Beetles, yeah!

... And star wipe and out.... LOL

Hey Pyro, good to see the system all together and running...

You might want to look at your stocking level though 150 Jades will be way too many for the system, I'd be thinking more along the lines of 50 or even less.

Actually I want more fish tanks!

Phase 2

The extension to the tunnel will soon hold 21 DWC Beds and close to 8000lt water in system. This will use about 1/4 of space available to expand. Not counting the nft system on the fence. The video is part one

Do you happen to know the feed conversion ratio for Jade perch? I only have a FCR for tilapia of 1.7kg of feed per 1kg fish biomass increase.

ummm - dammmmm - very nice my friend - very nice

Really impressive system Pyro, well done!


I may have misunderstood your post Pyro, but I think what EB is referring to is your capacity of bio-filtration, as your current system's growbeds won't have enough to support your fish stock at full size.

The experts tell us the balance to look for is the ratio between fish and grow media, rather than fish and water. In order for the fish waste to be broken down and converted, it needs beneficial bacteria, which will be growing on your grow media. Less media means less bacteria to convert the waste.

In reference to expansion, they say DWC doesn't provide any extra bio-filtration either, so I would be thinking even with all the DWC's, your system will still benefit from some extra grow bed media somewhere or other filtration.

I'm sure someone will correct me if I'm wrong Just trying to be helpful.

Keep the updates coming, it's great. Thanks for the details on the poly tunnel also

Thanks idzy you have been very helpfull
Poly tunnel is not perfect I need to make more clips for the ends and the rammed gal pipes for the extension will need to be longer by at least 900mm for extra stiffness its been breezy here with the almost cyclone and all . Also I used plastic coated wire for the bracing, DONT it stretches a lot! And make sure if your spans are longer than 6m to weld your rebar well, 2 of mine failed first time... but they won't fail again
I do agree with your assessment of my current bio-reactive surface area for 150 (full size? Just what do we call full size anyway?) jades.
My question about the feed conversion ratio was to get an idea of the growth rate of the fingerlings in other systems so that i could estimate the time to add more bio-reactive surface area, sorry I don't appear to be communicating well here .
On arrival 150 x 20g fingerlings will be about 3kg biomass. According to the Filter bio-media calculator on this site .9 cubic meters of media (i have assumed that system volume in the spreadsheet refers to media volume and Current 3 bed capacity is .9m3 ) will support a standing crop of 27kg of fish biomass at low density or only about 34 x 800g fish (If I have this wrong please please please tell me now!) so to reach low density stocking rates my fingerlings would need to double in size 3 times before a crisis could potentially occur. The current DWC bed was supposed to be a media bed (the 4th) but sump lacked capacity for 4 dumps and I'm out of IBC's for now and will most likely be converted to a gravel bed when sump capacity increases.
I'm looking to get 12 more IBC's this week, if I can get it past the war minister .
I have had Dutch style and heavily stocked aquariums for about 25 years and have constructed a few Denitrification bioreactors in the past I would be grateful if any forum members could help with differences, if any, in systems for aquaponics?
Not sure it is fair that they say that DWC beds add no bio- filtration, as all surfaces that are wet and oxygenated should be populated with Nitrosomonas and Nitrobacter, they will just have a hugely smaller relative surface area to a media bed, but I take your point.

Ultimately the balanced carrying capacity of a system like an aquaponics system has to do with the removal of the nitrates. Nitrates are the end result of the bacterial breakdown of Ammonia and Nitrite from fish wastes, generated by nutrient inputs in our case from added fish feed, given that sufficient water flow rate, pH, oxygenation and surface area exists for efficient microbial bio-reaction. This system nitrate removal for us, is the harvesting of our plant crops.
I have seen formulas for calculating stocking rates based on grow bed surface area and fish feeding rates to supply nutrients to this square meterage of grow bed, but surely this depends on the rate of growth (rate of plant biomass increase?) of the selected crop as this will vary greatly for different plants. Has this been debated before in here?

Cheers
pyro

Looks great pyro. Cant wait to see it after the expansion!

Hey Pyro, Nice setup and great video. What brand was the paint that you used?