Backyard Aquaponics
A place to discuss aquaponics

Thanks for all the great points.

the drain pipe into the fish tank was going to be plumbed into the side of the tank but the amount of fall was worrying me. And VB your dead right, skimping on the height of the shade house is pretty silly when grow beds are expensive, so will relook at that, maybe lift the grow beds up higher.

I'm not sure about which shade cloth to use. Obviously we get a lot of hot days and shade is pretty improtant for us to be able to keep growing through the summer, but to keep production going in winter we don't want too much shade. That was why we planned on the northern wall being opened up in winter. The shade cloth needs to be thick enough to block the wind a bit.

Les, you know we never even considered the space savings we could have by changing the growbeds to a east west orientation! Makes a lot of sense and really I think that plants getting enough sun is not going to be an issue for most of the year.

The trouble with planning a system now is that it is raining and green and cool and lovely. Most times it is not. We should plan the system during January with a dust storm blowing!

Hi Chrissy,

Do you know what your solar angles are? Ie the angle the sun is above the horizon on the solstices and equinoxes. If you don't I can calculate it for you if you give me your latitude.

Stuart

Chrissy, we're using 70% shadecloth, cos it's too hot and sticky for most of the year to not shade the plants that much.

We have Nitrate!!!

System #1 has been cycling now for almast 4 weeks. THis morning test results were ph8, Ammonia 4, Nitrite5, nitrate 5. These seem a bit high to a newbie like me. There are now 6 small yabbies in the tub. They didn't get fed yesterday, we have been feeding them very minimally. There are plants in the system, some sweet potato going great and tomato & Lettuce seedlings that have not grown for a few weeks.

System #2 has 7 small yabbies in it and no plants. It has been cycling for 5 days. Test results this morning were ph 7.8, Ammonia 0, Nitrite 5

Did I read somewhere that eggshells bring ph down? should I be trying to lower the ph?

Chrissy

Eggshells would bring pH up. Establishing the nitrogen cycle will bring it down. I would say leave the pH alone for now, but your ammonia and nitrite are too high. A water change would bring them down. If they stay high for too long, you will get disease in your livestock. It causes stress.

Chrissie, the eggshells will act as a buffer around 7 - 7.2, but your immediate problem is as Janet says - get the ammonia and nitrite down by changing some water, like 50%.

The tank should be close to cycled by now with the ammonia taking a dive to zero, nitrites should follow in a day or so thus completing the cycle

Just went back and checked system#1, is that still the 80 litre container?

System #1 is the foam box for plants, I think about 40 odd litres, and the plastic tub which may be 60 litres for the yabbies

Right - do some water changes to get the am down, Steve did a thing with PH to ammonia and nitrite reading, think you should get the am <1 by doing a couple of 50% changes over a day period - are you very short on water???

No, heaps of water, the dam at the back of the house is now full and we're using that water in the system. I have been doing fairly regular water changes, especially prompted by when I find a dead yabby, whoops!
Am i correct in thinking that now we have nitrate we must have bacteria?
Just find it a little difficult to fathom, that gravel lying out in our baking sun, add water and there's the bacteria! I guess using dam water could help????

Yep - you have bacteria but not in large enough quantities to convert all the ammonia etc....YET! Keep the levels (ammonia and nitrites) down by water changes and activate the "P" word.

Be patient and watch firstly for the ammonia to hit zero, followed closely (day or two) by the nitrite level. Your nitrates will slowly increase and PH will start to decrease, which is another HSM scenario

Must have been off lurking elsewhere when the doses of "P" were handed out!
Thanks Les, Will try....

chrissy ammo is of particualr concern at elevated ph like yours.

Strage, system two seems to have progressed further than system one in 1/4 the time....................

Steve,
System 1 has been up and down a bit:
10/3 Ammonia 4. Nitrite and Nitrate 0
15/3 Ammonia 0.5 Nitite and Nitrate 0
21/3 Amonia 4 Nitrates 0
26/3 Ammonia 4, Nitrite 5, Nitrate 5

I have done a few water changes which is probably what is behind the fluctuations I guess.

Chrissy

OK, I need some help if anyone has any ideas. We put 200 SP into the fridge system on 14/6 and started losing them about 3 days later, one or two a night, but now they are dying off seriously. Probably up to about 40 now.
Water tests have been consistantly nitrate 20, ammonia 0.25, nitrite 0. Ph 7.0.
I was blaming it on the cold as the fish came from australian native fish nursery in Qld. our water is getting as cold as 6 but warms up to about 12 each day. They haven't fed that i have seen since they came and apparently I am using the same food the hatchery used. They are not losing fish at the hatchery out of the same group that these came out of and they are perplexed as to what it could be.
I took out 40 yabbies and 4 yellow belly the day before the sp went in. The yabbies and YB had been doing really well.
We also put 300 of these sp into a dam but can't really tell what's happening there.
These ones tend to just get a bit slow then die and lie on the bottom.
There is no sign of gulping, the fridge has 2 drains running into it from the grow beds, on a timer. Have tried turning the system off overnight and covering the system but has made no difference.
They were just dying overnight but now they are dying constantly.
Any ideas?
I was thinking of just putting them in another dam but then I wouldn't really know if they got better or not.
Help!
Chrissy

Chrissy, whack a heater in there and see if that helps. It wouldn't need much if you only have a few hundred litres. The cold may well be stressing them out. Sudden changes in temp are a fish killer.

How much water do you have the 200 silvers in? How much growbeds? What sort of ammonia test do you have? are you sure it is accurate? No oiffense, but 200 seems like a lot of fish in a fridge, did anyone tell you that would be okay or did you just take a stab at it?

Mate, can you give us an answer on the above q's and we'll go from there.