View Full Version : goldfish dying

06-27-2013, 03:53 PM
I'm new to auaponics. Here’s where I’m at currently…

System is now 2 ½ months old and the nitrites peaked and then went to 0 about 4 weeks ago.
PH is 7.6, Ammonia is 0, Nitrites 0, and Nitrates 0
16 cf grow bed filled with pea gravel
75 gallon fish tank
Cycle via pond pump and bell siphon every 35 minutes.
100 gallon air pump and stone
Krill Fish feed

Problem: I stared stocking my tank with more and more large feeder goldfish (about 1.5” in length on average).
My goal was to get to about 350 with the assumption that this amount would be roughly 7 lbs. of fish (1 lbs. of fish for every 10 gallons). But before I got to 350 I noticed that my goldfish were starting to die at a rapid rate (10-20 per day). I did a little research and it seemed that they were infected with Ick or Ich. I went to the pet store and bought a plant friendly treatment and a tank heater. I did as instructed (added the treatment to the water, heated the tank to 80 degrees and also added new fresh water for about 3 days). I’ve used all the treatment, but am still seeing a loss of 5-10 fish per day – I’m now down to around 100 fish.
I spoke to Oliver at aquaponicsusa.com. He suggested I post here to get some advice. He did think that I may have loss of fish for a few other reasons besides the infection/parasite. Possibilities could be not enough air to the tank, and not enough feed for the fish (I was feeding them 1 teaspoon of food twice a day – based what I was instructed at the pet store).

Any recommendations would be much appreciated.

Thank you!

06-28-2013, 05:52 AM
i'm not sure where you got the "!lb per 10gallons" (my guess is from an aquarium guy?) a krill only diet won't be the best thing for your fish or plants either.. get a quality fish food, for goldfish i'd use lower protein fish food (same as catfish/bluegill)-i found a purina dealer near me that orders whatever i want, and it has always been less than $1/lb
base the fish load on the amount of filtration (volume of your growbed)
for every 100 gallons of growbed you can grow out up to 20lbs of fish in a newer system (thats the final weight, not the starting weight)
so, i think you're overstocked
i know you're only raising goldfish, but don't use treatments for aquarium fish, most are not meant for fish or plants that you intend to eat.. this is really important, and it's a common mistake.. but i wouldn't eat anything from a system using (most) aquarium chemical treatments..
for your fish and the ich problem, salt to 3ppt (1 gram per liter) - use pure salt (kosher salt is ok) but not iodized - there may be "anti caking" agents in table salt that will harm fish..
i'd probalby up the pumping to more cycles as well (every 15 min)

06-28-2013, 09:15 AM
I don't know what you did but it's pretty difficult to kill a gold fish...they are very hardy creatures and can withstand most anything. Remember that most people thing they can survive in a small gold fish bowl with no filtration and without ever changing the water, but not so.

Heed Keith_r's advise. I use pure sea salt myself which can be found at your local grocery store. :mrgreen:

Aloha Don
06-28-2013, 12:10 PM
I lost goldfish before because of an ammonia spike....have not lost any since water change
This does not seem to be your problem and it never hurts to add more DO to the system.