Shrimp Tank

[granzow1]

I'm new to the world of salt water aquariums and it appears that I am attempting something really complex out of the gate.

Some background is that I visited a shrimp farm that grows salt water shrimp for eating. I didn't visit the farm in the attached link but one very similar to this one http://rdmshrimp.com/. The farm had about 10 1500 gallon swimming pools with about 3000 shrimp in a pool.The tanks that they grew the shrimp in never had water changes ever, the waste/food/and bacteria stayed suspended in a slurry with high amounts of aeration...

I decided to try my own version with a relatively small 250 gallon tank, except I wanted to keep the water clean like an aquarium... so I copied the system that I saw at the shrimp farm but added some things from traditional salt aquariums like a fiber filter for mechanical filtering and a moving bed biomedia filter for nitrogen filtering.

The more I research the more confused I am on the topic of water changes. The farm I visited never ever does a water change and the shrimp grow fine in the unclear water. Yet if I was going to have a traditional salt water aquarium I would need to do a weekly water change even though the water is cleaner? I understand the nitrogen process and the importance of getting rid of ammonia and nitrite, and the fish farm said the shrimp can handle high levels of nitrate.

Another question I have is about cycling this tank. I've been cycling without fish and dosing ammonia, I've been cycling since June 10th. It took 35 days to get trace Nitrites, then it took me another 14 days to get Nitrites at 5 ppm. My problem is I'm now at day 66 and my Nitrites are stuck off the scale. I've read some people say that my tank will get through this process without a water change but I am wondering how long I need to wait or if there is something that I can do to help the process? At the first sign of my tank getting stuck I slowed the amount of ammonia that I was adding, but that didn't seem to help so recently I have been dosing to 2 ppm ammonia every 2 days and I also started adding Seachem Stability as it claims to grow bacteria that can handle high nitrite levels. Any information about no water change cycling would be appreciated.

[Reefmedic79]

I never change my water during the cycle.

That being said, as long as your adding ammonia to the tank the nitrites will likely continue to rise. All you needed is one dose of ammonia to start a cycle. By adding ammonia everyday or other day, our making your tank think the bio-load is increasing and in turn it is increasing the nitrites in the tank.

Stop adding ammonia, and in time the nitrite levels should decrease, but since the nitrites are "off the scale", you will likely want to go ahead and do a large water change if you don't want to wait another month or two for these extremely high levels to go down.

While these shrimp farms are not doing water changes they are likely dosing the tanks with some sort of mineral replacements, otherwise the shrimp would never grow, and while they can survive in high nitrate environments I doubt its optimal for the long term, as these shrimp from the looks of it are taken from larva to selling size in 6-8 months.

What type of shrimp where you planning on keeping?