Backyard Aquaponics
A place to discuss aquaponics

To read the start of my story viewtopic.php?f=45&t=6007

Since the end of last week I have had a number more deaths of the SP. A couple on saturday had a white fungas look about it so I salted FT to 1ppt and isulated the sick ones in a bucket with alot more salt and airation for a few hours. I thought they were going to survive but yesterday morning they were dead. Last night when I got home I found another 2 dead in the sump with no signs of anything wrong and now this morning I have found another 2 dead and they look perfectly ok. I have noticed with the ones that are dying they seem to be the bigger ones, the smaller ones seem to be alot more lively?? It seems that they slow down and they die!

I have a heater in the tank which I got last week as the water temp was getting down to 8 deg so that has helped bring it up to 12deg at night but water temp has been upto 19 during the day not sure if this temp swing is what is upsetting them or not??

My water test this morning shows:
PH 7.8
Am 2
Nitrite .25
Nitrate 5

If anyone has any ideas what might be going on or has any suggestions to improve my system I am all ears.

Temp swing can be bad
Ammonia of 2 and pH of 8 is concerning.
Do you have air in the system?
What kind of fish are we diagnosing?
Get that ammonia and nitrite down.
Is this an uncycled system?
The fungus is a sign of stress usually due to ammonia, low DO or low temps. If you have all three it's almost guaranteed.

My Koi developed a fungal looking growth similar to what you describe when my trout tank crashed. Salt, TLC and slightly warmer days seems to be bringing them through.

If it's only the bigger fish, it's one of two things, low DO, they need more air, or a longer term problem, like ammonia.
Without more info I'd lean toward DO and temps, but high ammo with high pH is definitely not good, the higher the pH the less ammonia it takes to become toxic.

Sounds like your fish have Saprolegnia (fish fungus) which often comes about with sharp drops in water temperatures. Winter is not the ideal time to be introducing Silver Perch to a new system with water temps as low as you have. Where did the fish come from and what water temps were they in??
Sap is usually terminal if it gets in the gills and spreads easily between fish. Salting may help and so would raising the water temp but once established is difficult to erradicate.
Good Luck

Would it be better if I put them in a seperate tank and keep it warmer? It warms up nicely during the day but its a battle to keep water warm durning the night as it is cycling all the time which is only bringing the temp down?

The water temp in the FT and the sump is of course exactly the same but it will be particularly the sump water bringing the overall temps down I expect.

Is the temp swing of 10-18 in 24hrs a bad amount of temp change?

SHould the heater be off and leave everything colder with less temp change?

The gold fish don't seem to care at all its the Silver Perch that are dying but then again I have only had them less than a week as well??

They came from Glenburn and were in 17deg down there and was around 13deg when i got them and put them into about 12 deg at the time.

I wonder if the temp of the water in the main tank is exactly the same top and bottom. I know when heating water that hot water rises leaving colder water down the bottom. Has anyone got any ideas on that?

Got home tonight and no dead fish !!

Have run a line from the air pump on the FT download to the sump so they have more air than the just the drain pipes which drain every 5mins or so.

Also put some rocks in the sump too to make it a bit more secure for them. Do you think that will help?

As long as you have air you can stop pumping from 6 pm to 8 am that will help with the temp swings

But this is a system that has not been totally cycled yet. Read dying fish in New AP bath system!!! I understand cycling up in cool weather is tough.

I would recommend running the heater at night and not in the day so the temp fluctuations won't be so extreme. Now if your system was all cycled up, I would agree that leaving the pump off overnight would help with the temps but since you are not cycled, I'm not so sure that shutting down filtration overnight is such a good idea. Definitely stop feeding till that ammonia reading gets down below 1.

I would probably say to salt to at least 3 ppt. (be sure it is pure salt and not table salt that might have anti-caking agents or iodine in it.)

Is this an outdoor system? Can you throw some sort of cover over it at night to help insulate? Blankets or tarp? Even some greenhouse plastic maybe?

I would hope the heater is temp regulated, so it can be run 24hrs no harm. If so, set it's thermostat to lower than day temp and leave it, otherwise switch it off during the day.

+1

You're just going to have to suffer for a bit and hope your bacteria get a move on. Try and warm it up using whatever you can (e.g. can you run some black polypipe through a sunny spot??) - insulate the tanks if you can. I have always been under the impression that a 5 degree water temperature change over a day will stress fish. I dont know where I got the number 5 from though.

more than 2-3 is the figure I had, so 5 would stress fish imho, but I have nfi where I got that from either...

I have just checked now and water is 14 deg. Heater is on. Have covered up sump as it is the only thing that is not in the hot house and subject to cold the most. So will see what the temps are in the morning.

Some kind soul gave this chart to me, and in case you don't already have it. Here you go.

This chart shows the association between ammonia, temperature and pH. At your pH, and because you are trying to control your temperature for silver perch, the ammonia becomes toxic at very low reading.

Be careful what rocks you throw into your system. From reading previously, some rocks increases the pH, again lowering your ammonia toxic level.

Yes I have this table thanks.

Water tests this morning after putting cortz? rocks in the sump 2 days ago and using low ph test not high test
13deg
Ph 7.2
Am 3
Nitrite .25-.5
Nitrate 5-10

1 dead fish looked though?

Not sure if the rocks have lowered my ph or it has been at this because I have only been using the high ph test

Another thing I noticed as I drank my coffee watching the fish this morning was wondering if the fluctuation of the water level in the sump could be affecting anything?? The sump is 400 deep and level goes between 200-300mm every few minutes not sure if they stress out about that or not.

The goldies seems to be really on the move more than they used to be last week. Not sure if thats because the water is now hotter than last week or because I have'nt fed them for a couple of days.

Quartz is silicone dioxide and completely stable in AP, so should not affect ph. If it is limestone or marble it will raise it to about 8+ slowly. Concrete block or similar is a really strong fast dangerous way to raise ph.

That ammonia of 3 is scary. I hope you have stopped feeding.

Sump level should only affect fish living in the sump. I haven't bothered reading your other thread, but I assume that at most you would have a goldfish or three in there.

Good luck!

Well actually I have 20 Goldfish and about 70 small SP in the sump. I planned to take out the SP in a month or so when they start to get a bit bigger and put them back in the main tank. Being new with fish I wanted to be able to see them and make sure they were ok. Should I put them back in the main FT now that it has cleared up a bit?