Aquaponic Gardening

A Community and Forum For Aquaponic Gardeners

Since I was responsible for a sizable kill here at work last Friday I figure I'd let others know where I went wrong.  Realize that I am in a much different system(flow through) than most of you folks here and so treatments are quick and highly dosed.  In fact I have a 10 minute retention time in any one tank.

So what happened: (this is the report I turned in)

Week prior:  Heavy rain caused yo-yo effect on temperatures of spring.  Water also became cloudy on several occasions.  Temp range 13.6-15.9 over the course of hours several times as most extreme storms passed over.  Oxygen dropped below 60% on Thursday when water warmed, so oxygen was added as well as additional flow from pond water source.



4:00pm- Notice colonies of what appears to be a fungus in irregular shapes on about 60 % of fish in the B-line.  Appetite of fish seemed to be reduced, some food on bottom.  Applied ¼ teaspoon of potassium permanganate to each head tank and 1 tablespoon to the main head tank.


8:00am- No deaths from treatment.  Little to no improvement on situation.  Decided to try 35% h202 at a rate of 1.5 gallons per raceway, given in head.  Also added 4 gallons (4 gallons at time with 10 minutes between doses) to head tank after all raceways were treated.

9:00am-  A few fish start to look stressed.  Added 50lbs of salt per tank to length of tank to attempt to calm them.

9:30am- Fish in the 4b look extremely stress, colors of fish changing.  Took DO in QZ in the bottom of B and A and found both in the 140s%.  Tried to drain water faster by turning on geotube pump and pulling standpipe.  This had no effect.

11:00am- majority of fish in tank 4b are dead.

12:00pm- Deaths taper off, some fish come back from the death on bottom of tank 4b.


Bottom line: treatment was too long, at too high of rate for the last raceway while the upper tanks were fine.  Furthermore, fish with disease were too comprised for this treatment.  The A line had little to no death in any tank except for the last unit.   

Views: 187

Reply to This

Replies to This Discussion

Bottom of tank with worst kill.
Sorry to hear about your awesh!!. I have been there as well. Have been watching your system because it is very different in that it is not closed loop. Wonder if maybe there are too many variables with your operation. Not a critic at all just curious due to everything is different from water input to raft selection. Good luck and keep us posted.

This was my fault, not a system fault.  The serial raceways just added to the potential that I would make a mistake.


The system is actually quite simple, and works fairly well.  It would be exponentially better if I could cover the spring, but that would be way too expensive.


Total loss was 959 lbs and 586 fish.  Still less than 10%.

I think I just shed a tear after looking at those pictures.  Sorry for your loss & thanks for sharing the advice.  It reminded me I really need to go fly fishing sometime soon!
Yes its pretty sad, but it more sad if others can't learn with me.

Reply to Discussion


© 2024   Created by Sylvia Bernstein.   Powered by

Badges  |  Report an Issue  |  Terms of Service