Backyard Aquaponics
A place to discuss aquaponics

Hey,
Wondering if anyone can help. I have had my rainbow trout fingerlings for about 8 weeks now. I am just at the end of cycling. In one of my FTs I have about 12 in there and two of them have not grown at all, they are black and I can reach in and pick them up from the bottom of the tank, they are very lethargic. The rest in that tank are growing well, have nice rainbow colours and are lightning fast.
Ph is about 6.0, nitrites 0.25, ammonia 0, nitrates 80
Has anyone seen this before?

Ive done a brief look around for a pic of your system but cant find one. It does help for us to look at what system you have and hopefully come up with an answer.

The usual questions come to mind..

system design
stock levels
temps
weather
age of your system
anything added recently
oxygen


In the past when I have had trout that are swimming slowly, lethargic and dropping down etc they are usually very close to death.

The colour of them could just be their gender. Ive grown out darker coloured ones to later find out that they were males. As they get older the bottom jaw hooks upwards and when I harvested mine they excreted milt.

Thanks Charlie,

Still getting around to getting some pics up. Definatley not over stocked, water temps between 9deg and 15deg.
I did add some Iron Chelate to the system as my plants were yellowing.
It is a new system, in a green house with plenty of oxygen.

i had one of mine be very lethargic and seemed quite dark in colour when it was still swimming... unfortunately it didn't survive but it was eating well (fat gut).

I hope yours don't end up like mine did