Bio-Spira vs. Stress Zyme

Its all up to personal preference and personal experience. Anythings better than Cycle. Id go with Spira though http://fishstoretn.com/bio_spira.html, youd have to wait a while (nov 8th) before its available again. so you could use the stress zyme till then
 
Bio Spira is the only true instant cycle product. I have used it 3 times with excellent results. You add the bio spira at the same time you add a full bio load of fish. My experience was always exactly as expected. The last time I used it was in an emergency situation in a 100 gal. tank, and I had to move all my fish to a 55 temporarily until the bio spira arrived 3 days later. I drained the 100 gal. after removing the fish, added new water, and let the filters run. When the bio spira arrived, I added it to the tank, and immediately added my 2 oscars, 2 jack dempseys, and 1 large pleco back into the tank. That was in June 2003, and I haven't had a problem since. Stress Zyme is not an instant cycle product. It may help accelerate the cycling process, but I would not recommend using it with a full bio load of fish. If you have another tank that is already cycled, you could also borrow some filter media, or gravel from the cycled tank to help you cycle your new tank.
 
Stress Zyme does nothing permanent for a tank so don't waste your money on it. If it a bacteria product that doesn't come refridgerated then stay away.
 
Note that Cycle and/or StressZyme will add nitrates to your tank, making it difficult to know how or if your cycle is progressing. If you show elavated nitrates, does that mean you have nitrifying bacteria or were they contained in the sample you added? That stuff is junk and it makes it trickier to know if you have a cycle occurring in your tank, IMO.

Jim
 
It won't hurt your fish but really won't do anything for the long term stability. Those products contain certain kinds of bacteria that eat ammonia. But not the long term colonizers that convert it to nitrite. That is why it is required to be added with every water change. A true bacteria product would be added one time (such as bio-spira) and never again. I wouldn't bother adding any more to your tank but wouldn't worry too much about the stuff you already added.
 
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