API QUICK START Freshwater and Saltwater Aquarium Nitrifying Bacteria 4-Ounce Bottle

Seems to work. Don't really know how to tell if it's doing it's job.

Works great

a useful and helpful product

Works perfectly

If you are using this to help cycle a tank, take the time to figure out how much you need per day/week over 6 weeks for your specific aquarium. It does work and I would use the whole bottle in the time it normally takes to cycle. In other words, this isn't a product you "keep a little for later."

I replaced the filter in my already well established tank, and yet I still got “new tank syndrome” ..this cleared the cloudy water within two days! My water is crystal clear again!! I have a shrimp only tank, and I love that this is shrimp safe, so far no shrimp have passed.

Works great cutting Ammonia. Keeps your fish safe keeping the water clean. Great value for the money because I only used one cap full in my 75 gallon tank to receive the benefits of using this product.

I had a sudden Nitrite spikes due to warm weather, it really warmed things up and nitrites just kept coming back in high high levels in under 4hrs after a 60% water change!!On the second day, the bacteria from this product established itself, and completely ate up all nitrites and for the first time my nitrates are much lower too!!!I use tap water, I process it in a 5 gallon bottle before adding to my 10 gallon aquarium. I process with API super strength conditioner dechlorifier (1 drop per gallon no more no less if you want your fish to be safe, 5 gallon bottle, hence the 5 drops) and then i mix and then I wait 1hr.Once thats done i use a syringe and inject 5ml of Quick start into the water as well. (1ml per gallon, not drop) I mix and then wait an hour again, that gives time for the bacteria to colonize completely.Sometimes I just set it aside for days after doing all those things because I don't need the water in the moment, by the time I use it, it will be very dense with healthy bacteria.Overall I'm very very pleased with this product, I had 3 shrimp die from nitrites already, this product is a true hero, saved the rest of my shrimp and fish.