Help - 5 dead fish :(

[Burnbrae]

Hi,
We are in the sunshine coast hinterland, and the AQ set-up (balcony kit from Murray) has been going since the start of Feb. We washed out the filter from the inside aquarium into the initial water to get the good bacteria happening. Plants went in immediately, with a couple of decent sized gold fish from the inside aquarium. We got a few silver perch during Feb from the local fish farmer, and got 50 little jades about 3 weeks ago. They have all been greedily eating and appearing quite happy until the last week. At first we blamed this on the nights getting cooler.

The initial pH was over 7, but that has drifted down over the last month. It has been 6.6 for the last week, but was 6.4 this morning. I have noticed that when I add some Seasol, the pH goes up for a little while, and that it goes down after heavy rain (of which we have had a bit the last week).

It was only after the jades were added that we actually started to see any readings other than zero for the amonia, nitrites and nitrates. This also corresponded with me harvesting the lettuce and bok choi, so there were less plants to take up the nutrients. The next day, I planted many more plants, which seem to be doing fine.

The readings for the last week have been constant, until today when the amonia disappeared.

Test last week today
amonia 0.25 0.0
nitrite 0 0
nitrate 40/80 40/80

When the nitrates hit this level, we reduced the food to once a day, and have stopped completely now. The fish are not interested in the food at all, and even the odd leaf that I drop in is ignored.

The water temp has been dropping - was 20 today.

I went out and bought some more seedlings and squeezed these into the grow bed this morning. i beleive that the recommendation for high nitrate levels is to add another grow bed, but we need to see if there is enough sun on this block to make it worth the effort. My tomatoes ended up with a fungus from not having enough sun (according to the guy in the plant shop), and the snow peas are not doing that well.

I would appreciate any advice.
The local fish farmer does not keep jade perch as he says they do not survive the winter here. As there are 2 dead silves adn 3 dead jades, and the water temp is still 20, I do not think this is the problem.

[Castaway]

What about air? You are running the pumps 24/7? Plenty of oxygen getting into the system?

[Burnbrae]

Yes, the air pump that came with the system is running 24/7. The water pump too is running 24/7. My husband has played with the overflow to stop it slashing all over the bottom of the lid - it runs thru another pipe with little holes drilled into it

All the fish are however congregating at the oppositite end of the tank from the pump and the air stones - which is unusual as they normally like the corner behind the pump.

This morning was also the first time that I have noticed a 'fishy' smell.

[fishfood]

Just grab a broom and give the fish tank bottom a scrub to make shore there isent a buildup of junk there Sounds like water quality problem how is the tests

[Burnbrae]

Grabbed a broom and opened lid to give tank a sweep. another poor little jade upside down almost on the bottom of the tank. :(:(:( Very little junk on the bottom - just a bit of gum blossom that has fallen in. Amonia is nil; nitrates are between 40 and 80 (I am not good with shades of colour); nitrites are nil; ph is 6.4; water temp is just under 20.

[aussieap]

Hi Burnbrae.
Have a read here
www2.dpi.qld.gov.au/fishweb/14076.html

Could be the night time temps getting below that 17C as per the article above.
pH should drift down in our ap systems. You will need some Eco Rose to buffer back up to that 7-7.5pH. You might get some 300 watt aquarium heaters. This will keep the a bit happier at nigh over the coming cooler months.

fwiw I have had small silvers down to 8-9C over winter. It is probably a local strain thing tho and the northern ones may not be quite as temp tolerant.

[Castaway]

Eumundi is slightly inland (about 20Km) from where I live right on the coast so it would have a greater night time temperature variation. I have 60 Jade Perch all doing well (water temp 24C) so the temperature variations are not so severe where I live. The last few days have been cooler and I noticed the fish ease off a little - but they are still actively eating. If I where you I would take a close look at what is falling down from the trees above into your system and seeing if it has some influence on the health of your fish.

[Burnbrae]

We are now up to 11 dead fish - 2 silvers and 9 jades. Very sad. all teh jades at least had round tummies - so not sure if they ate too much, if this is normal, or if it is a symptom of what killed them. All were floating in the bottom of the tank, belly-up - which I have not seen before in fish deaths in our aquarium.

We did a 1/3 water change and the nitrate level is now between 20 and 40, adn teh 'fishy' smell is gone.

We also took the time to pull apart the pump and clean it - had not been done for a couple of weeks - amazing how quickly it gets yucky.

I am not keen on doing the heater bit - mainly cause a couple of years ago one went bad and we boiled all the tropical fish in the small aquarium inside. But I do realise that it will take a fair bit to heat the AP tank. But then I am not keen to lose any more fish. The silvers come from a guy about 2km from here, so I expect they should have been fine temperature wise - but then I expect a large pond would not get as cold as a fibreglass tank.

Yes, Castaway, I have been wondering if gum blossom is a good thing for the fish. I know they eat it, as until this week, they kept the bottom of the tank clean from it!

I am hoping that there are no new fatalaties in the morning.

[GaryD]

Stop feeding immediately. Jade perch will continue to eat past the point that is good for them. Stopping the feed will also assist with any water quality issue you may have.....although I can't see any issue with any of the readings you've provided so far.

[Dufflight]

Trees droping things in the water can affect your fish. Not sure about gum blossom, sounds like a native. Some of our trees have a habbit of protecting there area with toxins.

Also are you salting the water. Sea salt 1 to 2 ppt.

[Burnbrae]

Gum blossom is off some of the native trees that are between the AP system and the creek. I am thinking of getting some plastic to cover the tank to keep the stuff out.

No, we are not salting the water. I gather we should be. Forgive my ignorance, but what does 1 to 2ppt mean? We are using tank water (collected off our roof when it rains), not town water.

No more dead since we changed some water, but one is looking a bit sad.

[Dufflight]

1 to 2 parts per thousand.
1kg to 2kg per thousand litres of water.

It counters nitrite and helps prevent some fish nasties like ick. And the fish seem happy with a little in the water.

Sunray pool salt is what I use. If you read through a few of the system threads you find a lot of improvments after salting. The plants don't seem to mind a little as it adds trace elements. But some plants will not tolerate a lot of salt. eg Strawberries

[Burnbrae]

omg - that is a scary amount of salt to be adding!
I was thinking about maybe a teaspoon or two!

Are we to add it all at once (is about 900L tank), or slowly over a few days?

[Dufflight]

A lot of people dissolve it in a bucket of water and slowly add it. My system I just cut open a 25kg bag and dropped it in the corner.:D
900ltr I would probably add 1kg to start and see how the fish go.

[froggo]

Hi Burnbrae

I'm with Dufflight, salt it.

The hatchery where I got my silvers from keep their water at 5ppm, we don't want to hurt our plants so I salted my system at 3ppm.

God bless froggo

[Outbackozzie]

You need to know what your water temp minimum and maximums are over a 24 hour period.

Any tanks with more than 6-10 deg c variation over a 24 hour period, will kill fish.

A once off occurance (hot weather followed by a storm) may not hurt the fish much, but big variations every day will.

[Burnbrae]

Thanks for all of the information.

We will be sure to purchase some salt as soon as practical. Can anyone suggest a dosage rate per day

We have not feed the fish for 3 days, how long should we delay before feeding again. All readings have remained unchanged and temperature ranges between 20.

Unfortunately we lost another 10 fish over Tuesday Night after the 25% water change on Tuesday afternoon, thankfully there was no further fatalities Wednesday afternoon.

[Castaway]

Hi Burnbrae,


Can anyone suggest a dosage rate per day

As Dufflight says above


900ltr I would probably add 1kg to start

I do hope you find out what caused the fish deaths, whether it is pH, water temp or something they ate. It would broaden our knowledge a lot more. I hope the rest of your fish survive and that you don't become discouraged with Aquaponics.

Good Luck. :)

[froggo]

Hi Burnbrae,

if it's temp swings as OBO suggested it's difficult with such a small fish tank to prevent the large temp swing without some sort of insulation or heating.

I have a 5000litre fish tank and a 1000litre sump and the water temp takes days to change a degree

I have just killed 10 of my new trout because of poor quality air stones, so I can understand your frustration. If you have small airstones that were supplied with your airpump I would change them to bigger units. My stones were holding the pump back. Once I replaced the 4 stones in my trout/sump tank at a cost of of $6.00 there have been no more deaths and the pump is putting out more air and making less noise.

You said your temps were between 20 and?

God bless froggo.

[quachy]

Just had a very similar problem with a total of 7 silvers dieing. Most of my deaths were the smaller ones of the group, so I uped to food, salted to 5ppt and so far so goo. I also rigged up a hospital tub to do salt baths for fish that were looking a bit slow and sad. I put one in for 36hrs and it perked right up. Went back into the main tank and so far so good. It has been 5 days since I salted and am doing a 10% water change each day to get the salt down to 2ppt. So far the plants seem fine, even the stawberries. I too have that "fishy" smell. Thought that this was a normal thing?

Quachy

[Burnbrae]

We are now up to 32 dead fish in total - which is 50%, over the last 5 days. Very sad.
We got some salt this morning and are going to throw it in.
As 3 of teh deaths were in an inside aquarium, I think we can rule out the gum blossom or water temp issues. We ran the tests against the inside tank and the levels of everything are pretty much nil (it has a huge external filter). The pJ inside is more alkaline than the AP system.

the only constant between the two tanks is the fish food, so I have to assume that we may have overfed them. I am now wondering how long we need to leave them before we can start feeding them again.

We were given some fish food by the local fish farmer, which he told us to store in the fridge. The fish loved it, specially the jades, and ate heaps. I had thought it may have been because it was cold, but then Murray and Gary freeze duck weed for them, so doubt if this is the problem.

The guy in the fish shop said that having too much protein in the fish food will affect the water quality and cause fungus on the fish. A couple of the latest dead ones had some fungus on them - but the early deaths did not.

The water temp is between 20 and 21.

So fingers crossed about the salt. Now just to get something to measure the ppt :)

[Castaway]

Thanks Burnbrae. Thats a good lesson to us all.

I certainly will pay a little more attention to my cavalier way of feeding fish - especially when their bellies look like they are going to explode. Thanks for the lesson and the warning.

All the best with your remaining fish. :)

[GaryD]

The water temp is between 20 and 21.


I hope you've reduced feeding dramatically......almost to nothing.

At 16 degrees C, you can expect mortality in Jade perch......just because of the temperature.

Overfeeding at any time will be problematic with Jades but in cooler weather it's almost a certainty that you'll have dead fish on your hands.

Gary

[Castaway]

Earlier this year my neighbour left their small 12 inch goldfish tank with us to look after while they went on holidays. Inside the tank were two goldfish. The water quality was pristine.
I overfed the goldfish on day 2.
Day 3 I noticed both fish gulping for air on the surface. So I fed them some more.
Day 3 and a half -the Water started to smell foul and went a murky milky colour. You couldnt walk past the tank without noticing a bad smell.
Day 3 and three quarters - a gold fish went belly up. Dead.
The penny dropped and I did a half water change.
The remaining gold fish survived.

My question is: Did the fish die from overfeeding or bad quality water? Or a combination of both?

Upshot to my story is when my neighbour arrived back form holidays to collect their fish - I convinced them that they only left me with one goldfish to look after! :cool:

[Burnbrae]

Remind me not to let you baby sit our QP system if we ever go on holidays :)

[QUOTE=


I hope you've reduced feeding dramatically......almost to nothing. :

We have not fed the fish since Monday - so basically for 5 days. Should we still be giving them a sprinkle?

We added 1kg of salt about 4 hours ago, so far so good - just feels so wrong putting salt in a freshwater tank!