Backyard Aquaponics
A place to discuss aquaponics

Hi all,

I'm new to aquaponics and the forum.

I'm currently building my first system based on the standard IBC setup they have on this website. I had to get my fish yesterday (12 rainbow trout) before my system was complete. The expanded clay was in the growbed (washed and rinsed) and I was in the process of filling the tank when I put the fish in.

After a few hours of filling the tank I came back and noticed one of the fish had died and the others were at the surface and appeared to almost be gasping for air (I thought there would have been enough dissolved oxygen from the fresh water) so I quickly connected the pump to get some circulation happening. That was last night and I came out and checked them this morning and all of them had died bar 2 but they are now dead also.

I check all the levels today and recorded a pH of 7.8, nitrite and amonia had no recording, and nitrate was within acceptable levels aswell.

I'm not sure if they died from lack of dissolved oxygen or if it could have been something else.

There are two other issues I can think of. Firstly before I knew any better I bought 100l of the cheap Chinese clay and some of the finer sediments from it have made it into the tank. Also I was worried about clorine in Adelaide tapwater so I filled the tank with water from my parents rainwater tank and I found out later the container I used to transport the water was a secondhand drum my dad got from an abattoirs. Apparantly it was only used for skins so it shouldn't have had any chemicals in it but I'm not so sure.

Anyway bottom line is I really have no idea so it would be great if someone could offer some suggestions and possible solutions.

Cheers, Paul

Sorry to hear that all your fish died. As you describe it appears that a lack of O2 was the cause of death.

It is clear from this forum that trout are notorious for dieing due to a low DO content and requiring plenty of airation of the water. As you were in the process of filling your tank it is highly likely that your system had not achieved any balance in its chemistry and there may have been some substances which were using up the O2 in the water despite the circulation. (Either from the clay or rain water tank or secondhand drum). If you are determined to go with fish cycling (I did), run the system for a few days prior to getting new fish to settle out any O2 eating substances. If where you get the fish from is not far away just get a couple to check out the water first.

I doubt that the clay dust would have caused any problems as many people have had their fish swiming in opaque water before it cleared. It was probably just stress and a low DO. An air pump would also be a fantastic idea if you are going to continue with trout.

Sorry but putting trout into a brand new system will never work unless you only put one or two in. They need optimum water conditions which new systems do not have. Your system seems so new that maybe even chlorine killed them if you filled with system water

Sorry for your fish loss mate. I can understand why you wouldn't want to use the undrinkable Adelaide tap water. But skins come with a lot of possible poisons involved so I'd start over if I was you. Colchicine and other poisons need very careful cleaning - you don't know what was in the container nor how the skins were treated so your system needs VERY GOOD cleaning before you trust either your fish or your own health now.

It would help if you can get a range of possible contaminants that might have transported into your system so you know what to guard against. Colchicine for example was a tanning agent and used on dope plants to force polyploidism for extra dope strength was deadly in the 1st generation of plants - I doubt it is in use these days but some of the other chemicals in use might be slower in effect but no less toxic.

I live an an area we can catch trout in the wild. They like cold mountain water in rushing streams. That meNs the live in very high DO levels.

Sent from my GT-S5660M using Tapatalk 2

Its a good idea to put a couple of sacreficial goldfish in a new system first

Thanks for all the replies.

I think it probably was due to low DO but I'm still worried about possible chemicals from the drum. My dad clarified and said the skins he was talking about were actually intestines used for making sausages but he can't definitively say there was nothing else put in them as the drum was empty when he picked it up.

Journeyman how do you recommend I clean my system? I'm assuming I should start by draining the water. I'm mostly not sure about how to clean the tank and how to clean the expanded clay.

Cheers.

Hot water and detergent scrub rinse followed with bleach solution and leave in the sun for a few days.

Thanks Faye. Is it necessary to clean the clay as well and if so how would I do so?

We just rinse the expanded clay for about 10 minutes to remove most of the dust and direct the water with a pool hose off to the garden.

awesome, thanks very much!

Get a good scrubbing brush to do Faye's suggestions. I'd start with a metho bath, (mix with warm water around 1 litre to a 20L bucket. Scrub it around the surfaces, and drain it through the pipes that ahve been used. Rinse then bleach in similar fashion, rinse then detergent, then rinse with hot water until a glassful looks pristine. Check all detergent etc is gone by running some water through the system into a clear container you can close properly (e.g. screw top bottle) then shake the crap oput of it and see if you get bubbles or scum of any kind.

The metho is just because it removes things detergent and bleach will not touch. Given what you said your father said, it may not be needed.

cheers Journeyman, Ill get to work!

pHughes,

I would just run my system for a week and do as F&F suggested put in some Goldfish. Then if they live for a month put in your fish. From experience and what people report most have fish deaths in a new system. IMO a system has to run for 12 months before it settles down.

You can go through the cleaning process if you want, but still carry out the above.

yeah I agree. I just went and got a couple of goldfish as test specimens. Hopefully they make it!