Hi, I am building a several hundred gallon outdoor aquarium and plans for no filtration?

Question

I am building an outdoor aquarium of several hundred gallons and have lots of clear spring water to run through it, maybe as many as 8 to 10 complete water changes per day. I want to keep lots of fish. Can I change the water too much, will I be washing away all of the little microorganisms that little fish might feed on. Can the water be too clean? thanks

Answer 1

That should work wonderfully provided a few things are met. 1> that the water is the correct temperature for the fish you plan to keep 2. that other water parameters are comfortable for the fish (pH, hardness, etc) and that there are no fish living any where up stream from your tank. The last is important to prevent disease in your tank.

This system is used on a large scale by most aquaculture facilities, especially those dealing with trout or salmon. Google that for some more info on suggested flow rates and the like.

Hope that helps!

MM

Answer 2

If this is a natural fed spring, like a river, then you should be alright as long as the water is constantly flowing. Bacteria will grow in the tank and on every surface of the tank. The natural water will have beneficial bacteria in it already. Keep in mind the size and territory requirements of your fish. Each Koi needs 50 gallons mimimum of space, for example. You should not have a water quality issue if it runs like a stream. However, keep flow in mind as well. How many GPH will be going through the tank? Filters that are rated for 150 gallons cycle around 400 gallons per hour or more. Target for that range. if there is too much water going through, you could have too much turbulence for fish to be healthy and stress free.

start with a few fish and monitor the environment. Watch not only the water quality, but the way the fish act, the flow of the water, and how much space the fish have. Add fish slowly until you reach a comfortable limit. Do not overcrowd. Even ponds can become stagnate pools with too many fish.

Lastly, make sure that there is enough flow. If the water isn't agitated, then waste gasses can't escape. this can affect your kH and gH, which in turn can make pH fluctuate, which can affect how toxic the ammonia is, which can affect how nitrogen and other gasses are absorbed and released from the fishes system.... Basically, it's all one big cycle. Beware of still water at the bottom of the tank. It's like an oxygen sucking, bacteria producing pocket of death. The water has to flow through the whole tank, not just the surface. If you want to see how the water flows, add a little methalyine blue to the source and see where the die goes. To do it environmentally safe, you could use fine wood chips or a light grain. it's just a pain to remove.

I hope that helps...it sounds like a big, impressive, competely awesom project. Good Luck!

Answer 3

You can never do to many water changes.