Backyard Aquaponics
A place to discuss aquaponics

So now we are trying to work out what to do next! We still need a few more thou litres of water in the system for it to be at capacity not counting the rest of the FTs, but if we dont also fill the tops of the 2 tier tanks and just let them flow straight in to the bottom tanks we can add yabbies and start the system. Am so annoyed that when normally we would be thanking our lucky stars we have access to as much river water as we need, it may not be useable.

Would appreciate any thoughts on stocking rates if cycling with yabbies - were thinking of 1-200 (system max is about 350-400 yabbies when full). Is 100 yabbies enough to cycle the system? Should we just bite the bullet and go SPs instead?

One of the reasons we arent looking at putting fish into the 2000L tank yet is because when we purchased them they had been used for yabbies and have a circle of heavy plastic glued over the drain with holes in it. Weve found that when the pump is draining the tank it creates a fairly strong whirlpool effect in the centre which I think may hurt the fish, so would prefer to leave for now until we set the other tanks up and organise standpipes for all FTs once we can transfer water out of the one we are using.

Will be salting the system this week before adding yabbies, and considering asking yabby guy if we could aquire some of his dam water as well. Would spike the bacteria levels beautifully I think. Am hoping now that they will take barra food otherwise I see a mass yabby HSM looming.

Lost about 400L of our precious water leaks occured in 2 of the IBC bottom yabby beds that ended up draining out so have turned off those so we can fix when dry.

Apparently black water will be past us by next week which is good but main concern is still stagnant stinking water in pipeline - as no-one is irrigating due to rains, the water has just been sitting there going rotten. Only thing we can do as water board wont flush lines is wait for up to a month until people start irrigating again and clear the line

Blackwater has hit Sunraysia with a vengeance - and is literally black - even an inch of water looks like black dye has been added to it!... would be interesting if it wasnt so foul

Floodwaters have passed Swan Hill and are heading our way now, and Ive been told that where the water is coming from this time is clean - and therefore the floodwaters are also clean... hope they get here soon and flush the river.

See on the news just recentley black water from the barmah forest got into the murry river and depleted the oxygen and they were picking up giant murry cod a meter long dead along the banks

Yup have heard that recently - apparently theres been a few creeks etc. dammed off to try and save the gum trees by environmentalists, which has all gone toxic.

Had a letter to the editor in one of the local papers which was from one of the Aboriginal elders. Pretty much said that the calls from greenies for environmental flow was bullshit... the gums can survive for decades with no water and will look dead - then when they get water they re-shoot. Its the way its been for thousands of years. he reckons all the greenies have done is stuff the river and is disgusted with the government for creating an environmental catastrophy - I thought...good on him!

Had a mates uncle fishing upstream a few weeks ago with a 2 1/2 metre tinny - they found a cod 3/4 the length of the boat - mate saw the pics and cried . Apparently a lot of the cod and perch are dying - unfortunately the carp arent.

Testing our system water compared to the river water soon to see how it might go if added to the system - will post results...

Sorry about the above posts - should have put them in the Venting Corner Just been a bit frustrated!!

Tested both the System water and the water coming out of our taps today and the results were interesting.

River water coming out of our taps:

Ph: 7
Amm: .50
Ni: 0
Na: 0


System water which is rainwater only at this point - a bit over 6000L:

Ph: 8.3
Amm: .25
Ni: .25
Na: Tracing between 0 and 5.0 - reckon its around 3.0

Apart from kids weeing in the 2000L tank and our 1 remaining yabby theres nothing in there at the moment. Although there were yabby carcases in one of the GBs (pre gravel) for quite a while until we had time to clean it out, and when we got hit by the big rains it was overflowing into the system so it may be the reason for the spiking of the system but Im still surprised its showing anything!.

We are going to add river water to the system weve decided even though it stinks it looks like it may help spike the ammonia levels? (and I reckon the smell should clear from the gravel filtering and the system doing its thing?)

Interestingly weve noticed that when filling containers with the river water, its foaming slightly like there is detergent in the water... but think it must be high nutrient levels. I believe in Aquaculture that a foam fractionator is used to remove protein or suspended solids or something?? would this perhaps be similar? would it help or hinder the cycling process?

thoughts welcome and appreciated.

Had the electrician here today so now have an outdoor power point for the timer - will put it in this weekend some time. he is coming back over this way next week to wire up the float switches for the sump and the FTs so they dont empty themselves on us. Pumps arent made to suck air... and neither are the fish for that matter - so figured the more failsafes we have in the system the better!

Went to 'B' today and bought 21 packs of seeds ... didnt mean to get that many but figure we'll use them eventually

Going to start filling tanks tomorrow with the river water and might start dumping in seasol too... got 8 litres sitting there so might as well start using it up.

Will also chuck some seeds around the GBs and save some for seed trays. Working on a wicking propagation setup we can incorporate in the system as well.

Thinking of grabbing a couple of hundred yabbies next week some time and chucking them in too. Have spoken to a hatchery about 20mins down the road that has a couple of thou SPs, as well as Murray Cod and Golden Perch... Might cycle system first tho.

seasol wont fire it up you will need an amonia source to do that

If the tap waters Amm: .50 from the frothy organics and nutrients in the water, would that be enough to get cycling going?

The Murray has had two blackwater events, the first was caused by tannin from leaf litter etc, this was when the water was brown like tea. The bacteria that was present to break down this was what caused the deoxygenation and the fish deaths. The second event was caused by manganese from the floodplain. This was black and inky looking and has now passed Robinvale and the water is returning to the tannin color!

Thanks for clearing that up Tristrin. Weve heard so many stories but by the sound of that the worst is still to come! Would manganese be bad to have in the system though?

Actually when I was talking the other day about how black the water looked - an inch of water with black dye in it - I do need to clarify... It was more like a couple of drops of black dye... It looked dark grey but clear, and not cloudy and not brown like tea...

which interestingly is what its looking like today - more like STRONG tea...didnt really notice until the kids jumped in again and their legs under the water were dark orange.

Filled the 2000L tank today from the tap and it looked like this....(promise I have not added any seasol)

Actually Tristrin - weve decided not to add anymore river water to the system for now as we are getting another big rain event coming and are going to try to harvest as much rainwater as we can to finish off the system....

I hope you dont get hit too hard this time... will be watching the weather closely and you will be in our thoughts as weve been told it could be similar to the last downpour ... hopefully it will dump on us and clip you - but dont tell the viticulturalists I wished that on them

Exactly what I was wondering BB. Seems like it would help kick things off a bit, wouldn't it?

Hi Naz,
Hubby thinks the black manganese water has probably reached you by now. I have no idea how it will affect fish and would guess that the low concentration would probably be ok, but I would avoid using it if you don't need to.

We have also heard that we could be hit with another big rain in Feb. We have only just stopped pumping the water from the last event. We have a few plans we want to do to try and avoid so much flooding again, but they will take some time to implement. Maybe we should just build an ark