I have googled this subject I have spoken to a couple of fish farms no conclusive answer, my question is,
I have 2 very large rainwater tanks (really large) we use the water for toilets, chickens, veg
I would like to grow fish (ie carp or another suggestion) to eat, my tanks are underground so dark.
I don't want to trial & error as this would mean fish suffering for no reason.
I have 10 common carp and 20 small goldfish in a 1000L tank. I use them as part of my small backyard aquaponics system.
The tank is kept in the garage with no natural light. It's dark most of the time in there apart from a few minutes a day when I go in to check on them. The goldfish have been there for over a year and are doing very well. The carp have been in there for 8 months and are growing just fine. Most fish don't need sunlight. Think of how dark it would be at the bottom of a muddy lake especially if the lake has some water sports activity going on. The worst thing that happens to goldfish is that their colour fades.
It's a good idea for your tanks but here comes the rub... Goldfish are very hardy but any "real" fish for eating needs to be kept in the right conditions. You need to keep the water oxygenated and ideally you need to filter a tanks worth of water at least every few hours. You can oxygenate with a small air pump but will need to have a backup plan if it's mains powered to ensure the fish get oxygen if there is a power cut. For carp, think about 50L of air, per hour, per fish.
As for filtering, you have some very large tanks so you would need to work out how much water you use per day and how quickly it is replaced. You *could* get away without having to use any sort of pump or filter if you keep your fish stock very low.
Slightly off topic but common carp taste just fine if they are kept in clean, well filtered water. We had one out of our system just last week and it was very tasty.
Topic: Rainwater for Livestock: using fish? (Read 12786 times)
