Backyard Aquaponics
A place to discuss aquaponics

I second that - GREAT PIC!

Mark

Yeah, now that I look at it, it does look all right, the cheery toms taste awesome.

When this years photo comp is posted, i might submit it.

still harvesting silverbeat, cheery toms, broccoli, spinach & strawberries (still haven't acted on the Eco Rose yet)

my PH has stayed steady at 7.4, rites @ 0, Amm @ 0, rates @ 40, been holding these levels for a week now.
Will the higher ph help my strawberries??

Regards,
Matt

hay guy's
Been a few weeks since i updated!
here's some photo's of the system around week 17
toms are taking over the system, over the back is still the broccoli growing and about to harvest 2nd time around
the strawberries are still blobs but are much bigger.
only a couple of weeks till im out of here, I only have 6 goldies left due to the yabbies getting hold of a couple, got a nitrite spike at the time and could relate it to dead fish being consumed by the yabbies. Couple of days later back to normal.
Goldies and yabbies will be farmed of a to family member soon.


Regards
Matt,

guys & girl,
Over the past week I've noticed that my goldies are mainly on the bottom of the tank but when I came in to do some water test and feed them they are up and at the top gobbing the water.
This same week I've experienced fish loses (when I say fish losses i mean 4 but i only had 8 goldies left.) All the fish loses seem to be due to the yabbies getting hold of them. they all seem to be cut up or half eaten. even found yabbies with the goldies in claws.
as I've never seen them act this way i was wondering if any body else has had the same experience or could enlighten me.
I've attached a photo of the 3 goldies i lost over night. 2 look like a yabbie may have got to them and the other is just dis colored around the stomach area.
my water tests have been spot on except for the first dead fish causing a nitrite spike 5 days ago, but the next day was back down.

attached is a photo of the dead fish today and my water tests for the last week.

any info would be good info.

regards

Matt

Hi mattyry,

yes I've seen this before in a kids indoor fish tank.
In went a yabby one day and within minutes the yabby caught a goldfish as it swam past and started to eat it alive.

Lesson learned, never put small fish in with big yabbies or they will soon be gone.

God bless, froggo.

Looks like the 3rd goldie has suffered from a yabbie attack also, his tail is all eaten and the stress of the ordeal probably finished him off. How big are your goldies and how many yabbies do you have? I'm assuming these are in your IBC fish tank ie: 600lts or more.
My prototype system has 7 goldies about 70mm long and 2 yabbies in a 200lt fish tank. One yabbie would be about 70mm long the other 50mm, I have noticed some damage to the goldies tails but never seen a full on attack.
I have watched it on youtube though so I know it can happen. Ahh the cycle of life!

also your rising reading seem to go with the rise in water temp. How much aeration do you have?

bb,
i think its the middle one that had a discolored belly, actually it looked like it burst at the seams in line with the stomach, i'm wondering if he ate too much?? or maybe i feed them too much.
my goldies were around 60 - 70mm
only have 5 yabbies left, 2 or 3 are at least 120mm - 150mm
pretty sure my air is alright, but i must admit that i just purchased a pump with 2 outlets, without really thinking about how much air is a minimum?? what is the minimum?? my pump just says "ELITE 802"
went over the past 4 months of water test which show that my ammonia & rites have basically = zero most reading, and my temp has fluctuated from 20 - 29 degrees??
still i've seen the yabbies have a crack at the goldies when they get too close.
now that they hang around the bottom it more likely to come too close to the yabbies.

regards

Matt

Hi Mattyry.

From my aquarium experiences - yabbies and fish do not mix with happy endings - unless you want to see Murray Cods going the yabbies! On the ammonia subject - it should be zero at all times except during initial cycling. Symptoms will be fishes at the surface gasping air as ammonia and nitrite block the fishes oxygen receptors (is that a word?) and they will eventually suffocate (brown blood sickness I think it is called). You CANNOT overfeed fish - they will only eat as much as they want. However, they will always look hungry and will play with food before spitting it out (because they are already full). Then the wasted food simply pollutes the water causing ammonia/nitrite problems - which is the most frequent demise of aquariums in the hands of newcomers. Did you know a fishes stomach is roughly the size of one of the fishes eyes? Bubble eyed gold fish excluded. So they do not need much food.

I just posted my 1st AP system to the "New Systems" forum if you want to have a look - it has been a hoot putting it together. I am in Melton and I too will need some kind of shade in summer and protection in Winter like yours.

C'man.
It's strange that they have lived together for 4 months with out any issues??
any how when i get back from my holiday and build my next system I'm got to put the yabbies in the sump.

thanks for the insight.

Anyone know how much air is needed?? or have a ratio in regards to the FT size??

regards
matt

I had the same problem. My crawfish and koi were doing fine and then one day the crawfish started eating the koi.

What is interesting to me is the increase in ammo in your system. In my system, when the crawfish started eating the koi there was an increase in ammo also. I wonder if the fish get weak from the high ammo levels and thats when the crawfish start eating them.

I wonder which came 1st - the ammonia or the dead half eaten fish? Decaying organic material - fish in particular - can give off high ammonia rather quickly - depending on the water volume.

C'man

My first dead fish was first noticed on the 28th when i could see by the ammonia level something wasn't right. counted my fish while feeding them and noticed 1 missing, found another floater on the 29th with a big chop mark across him. then on the 1st i found 3 that are pictured with chop marks. hence you see the the ammonia pick up again.
all my levels have come back to 0,0,40 ph @ 7.4, had a few hot days this week but water temp didn't get over 24. harvested more Cherry's and broccoli, only 4 yabbies and 1 goldie left
Anyone know how much air should be in a given volume of water??

regards

Matt

Your flood/drain may give enough air, but more is always good, especially when the water gets warmer or power fails. Actual effectiveness of air will vary depending on the distance it passes through water and the size of the bubbles, but I believe something on the order of 4liters/minute is enough for 1000liters of water.

PS: don't trust those numbers....I said "on the order of" and meant it.

Those patches of red around the fins - are they blood at all (can't tell on that res photo)? Could be an infection. Usually infections are what kill fish (if it's not yabbies) but usually it's a secondary thing - i.e. something has weakend the fish such that can no longer resist the baddies - i.e. high ammonia, low oxygen, bad water conditions in general etc

Hi Matt.

Air bubbles add minimum oxygen to the water column. Oxygen primarily saturates the water body at the water to air interface (the surface). Sure, each air bubble also has its own surface area - but it is insignificant in size and it does not stay in contact with the water very long (bubbles burst at the surface). What they do do however, is rotate the water column for us - so oxygen depleted water at the bottom of your pond is rotated to the surface and the oxygen-rich surface water is rotated to the bottom - continously. So I do not know if an air to water argument is sensible.

In my system, I have incorporated a rather violent spray bar over my 4 x ponds (lucky I live on an acre - bloody noisy!) which agitates and rotates the water columns - doing a similar job to air bubbles. Plus the exposure of the water to air throughout the GBs will also oxygenate it well.