If the ammonia and nitrite levels aren't at zero soon I don't know that I would consider Cycle® to be of much value - especially now that BioSpira® is out stealing all the accolades. I'd rather spend $5 - $10 more for BioSpira® which definitely works - and in only 2-3 days (3 days for me). Some people experience a completely cycled tank in 3 weeks without any bacterial supplements - so for me - I cant see any value in Cycle®. Here's another point - The Nitrosomonas and Nitrospira will need food (ammonia & nitrite) in order to survive. There is none of that in a bottle of Cycle® and since Cycle® is kept at room temperature they will be active and quickly starve once they are put in the bottle. If it is not refrigerated then you are wasting your money. I saw a bottle with an expiration date of 2007. LMAO - that bacteria was already dead I assure you. The bacteria in BioSpira® is in stasis due to the low temperature of refrigeration and therefore will not need food until they get warm.
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