Backyard Aquaponics
A place to discuss aquaponics

Hi guys,

Quick rundown - 1000lt fish tank, 700lt sump, 2x 300lt growbeds (probably about 250lt media in each)

I had the system running for 3.5 months with 10 goldfish in it to start things cycling, 3 weeks ago i introduced 10 silver perch and 10 yabbies into the sump. Everything has been great, crystal clear water etc until 4 days ago when the water started going cloudy and the thin algae on the sides of the fish tank began to get a bit thicker.

Over the last 3 days ive pulled out 3 dead silver perch, most of the fish are very lethargic at the bottom of the tank and a few just mill around the top.

The 3 dead fish all have the same blood red colorings around the gills and under the mouth, i also noticed on the fish at the top of the tank they had a white film hanging off them.

I was thinking lack of oxygen, maybe due to the slight increase in temperature over the last week or so. Ive modified the pump inlet to jet water into the tank creating more bubbles, along with the bubbler i already have (i suspect i will need to upgrade this asap)

Anything i can do in the meantime to stop the rest of the stock from dying out?? I did a 1/3 water change yesterday.

All tests have been normal, PH 8.0, Nitrite 0, ammonia 0, nitrate -just off 0, and nothing has changed in the last 3 weeks except for the slightly warmer weather

Thanks for the help

James

Sounds like you have a Viral infection going on there.... You need to either carefully catch all your fish and put them in a Hospital tank with medicine in to kill viral infections, ask nearest reputable petshop or Koi suppliers which they can recommend or...
You need to separate Ft flow from the GBs. Then get an Airpump into the FT and start antiviral treatment. Off course you will then also need to look into modifying your waterflow direction from the pump so that flows to the GBs, and no longer to the FT during this hospitalisation period. Plants will need feeding with something like Seasol or Seagrow.
After adding the Meds at recommended dosages, you need to add some multivitamin to the FT water and after all of that, in about a week from now, with any living fish still.... You can return to normal. Best of luck Mister

Thanks for the quick reply! Ive put all the fish in a small tank with an air pump to keep them going for now. Any hints as to what treatments i should look at and are they ok for aquaponics fish?

Ive drained the fish tank as i spotted 4 more floaters this morning, sump and growbeds are still full so that the yabbies still have some waterflow.

So much for a cheap hobby that will save us money in the long run!

Thanks again
James

salt to 6ppm. maybe higher, im no expert.

yea i had the same deal with fish deaths and wondering how its cheaper than buying fish, you do learn that it isnt a "save money" hobby, it certainly does cost.

Looks like viral or bacterial damage.
Like Yav says above, tip the salt in ASAP, probably 4ppt for starters, then research safe max level for SP before adding any more.

Have a read of this: http://www.dpi.nsw.gov.au/__data/assets ... Manual.pdf

Be careful with any chemical (other than NaCl) treatments, many are not suitable for fish that you want to eat.

its that magic step from Goldfish to xxx that gets em mostly....

lot to be said for how hardy and cheap goldfish actually are.
if plain old carp were a great tasting plate fish we would be on a winner.....

They can be if you prepare them properly!

Yep I would do a harsh water change and salt to 4ppm ,
Try an put as much air or water flow into the tank,
What was the water temp at?

http://www.savemysickfish.com/symptoms/
This is pretty basic but this can help you troubleshoot mate

http://www.savemysickfish.com/diseases/ ... ndrome.asp
Maybe this one..
Cloudy water
New system
Smelly water

These are for aquarium fish but it's same thing.
Salting and water change are always good starting points

It looks like ammonia poisoning but you say all your parameters are all on zero????

I think the white film is probably fungal. Viruses and bacteria can move in if the fish are weakened. 20 fish and 10 yabbies should be fine in your system, and I wouldn't expect an Ammonia spike, unless there was a dead fish caught up somewhere. Are they all accounted for?

Water temp???

Thanks for the help so far. Ill do another water test tonight and throw the thermometer in to check Temps. I did notice that the worst looking fish are the goldies but the silver perch that are still alive are all swimming strong and with no cotton wool stuff on the skin. I put the perch back in the system last night but kept the goldies isolated in a smaller tank.

Fingers crossed it all comes good

Cotton wool stuff,,, it's not parasites is it

I am curious if this is related to the yabbies. If so, your problem may be violence in the tank. Yabbies are strong hunters and will attack fish many times their size.

If your water parameters are all clear, could be that the yabbies are attacking the fish at night time, causing the fish to be in a constant state of fear. Fish wounds will often get fuzzy white stuff on them that look like tiny little cotton balls. Judging by how clear the eyes are on the fish I'm not sure if it's illness as when a fish gets sick it tends to have dull cloudy eyes.

It's definitely a process of trial and error.

One thing I would suggest as you try and sort out the cause is to avoid medication at all costs. Most fish do not tolerate medication very well and might die just from the stress during that process. If you can remove all the fish except for the yabbies and move them over to a hospital tank, you may be able to observe more carefully how the fish are handling life away from the yabbies. If they are being attacked/bullied you will see an almost immediate improvement in their health.


The other culprit this could be is something called Costia, which can be eradicated with a combination of slowly raising the water temperature (1 degree F per hour) until it is in the range of the high 80's, low 90's. Combined with slowly adding salt should see your fish returned to good health. If this is Costia it would be best to move all the fish to a hospital tank as it will be easier to control the temperature change. I am not sure if Costia affects Yabbies, but as a precaution you could move them to a separate hospital tank.

Best of luck! I know how stressful it can be to deal with sick fish.