API QUICK START Freshwater and Saltwater Aquarium Nitrifying Bacteria 16-Ounce Bottle

The API QUICK START for freshwater and saltwater aquariums is a total game-changer—especially if you're setting up a new tank or adding fish to an existing one. It makes the nitrogen cycle process way less stressful, both for you and your fish. I used it when starting a new freshwater setup, and within 24 hours my tank was safe and stable. No ammonia spikes, no nitrite issues—it genuinely helps establish the biological filter FAST. It's also great to use after water changes, adding new fish, or cleaning the filter. What I love is that it’s super easy to use—just shake and pour. The bottle gives clear instructions, and the results speak for themselves. My fish were active and healthy from day one. This is one of those products you always want on hand. It helps create a healthy environment and gives peace of mind whether you're a beginner or a seasoned aquarist.

Must have for any fish tank owner! Great product and good bottle size for the price. This is my first refill - the first bottle lasted me nearly two years.

Works well to make tap water safe for fish.

Good product if you can't wait for your tank to cycle naturally.

This is the ONLY THING I USE FOR MY TURTLES to keep they BIOWASTE DOWN AND MAINTAIN THEIR NITROGEN CYCLE. This product works wonders and i highly recommend it. This product is SUPER CONCENTRATED so you only need to use it AS THE BOTTLE RECCOMENDS!!!!! TRUST ME ON THIS!!!!! I have 1 turtle and 2 bettah fish and i use this product for both tanks. ANYTHING WITH WEBED FEET HANDS OR GILLS REQUIRES THE NITROGEN CYCLE and this product does EXCELLENT with starting the cycle and MAINTAINING IT keeping NITRATES AND NITRITES DOWN TO A VERY MANAGEABLE LEVEL and keeping down the SMELL OF AMONIA IF ANY!!!! so anyone with fish or turtles like me..........BUY THIS AND THANK ME LATER!!!! ENJOY

Have used Quick Start on two tanks now, one 10 gallon and one 45 gallon. The product works, BUT it has to be used in the right way (which isn't the one printed on the back label.) The first time I used it on the 10 gallon was my first time setting up an aquarium, and I pretty much just dumped the recommended dosage in along with conditioner/stress zyme, then put in fish the next day. After about a week or two my ammonia levels spiked hard, then another one to two weeks or so after that my nitrites and nitrates started to spike. Ended up losing 50% of my fish before the cycle finally stabilized (the remainder have survived over a year now). The problem is that the cycle needs ammonia to start, and a brand new tank will not have any, nor does Quick Start contain ammonia. Therefore, if you just dump it into a new tank, then put in fish, the cycle will not start until the fish food/waste starts to decompose into ammonia, which can take a week or more. Once sufficient ammonia is present in the tank (3-5ppm), it takes about another week or two for the bacteria to then break it down to nitrites and then nitrates, completing the cycle. During this time your fish will be suffering high ammonia and nitrite levels, even with frequent water changes. To properly cycle your tank with Quick Start, you need to introduce ammonia into the water quickly and without fish. The "natural" and slower way to do this is to put biomass into the tank and wait for it to rot. This can be store bought fish (not live), shrimp, fish pellets/flakes, etc. However, these take time to decay. The faster way to introduce ammonia is to directly buy a bottle of liquid ammonia designed for cycling aquariums, and put in enough to reach 4-5ppm. Then immediately add API Quick Start, along with any conditioner/etc. After about a week or so you'll notice the ammonia levels go down, and nitrites start spiking. After another few days the nitrites and ammonia will both go down close to or at 0, and nitrates will be present. Now the tank is fully cycled, and it's safe to add fish.

I learned THIS PROSUCT is so usefull I use it for adding water to my fish tanks and also for dechloinating water i use to water my sensitive house plants and my newest discovery It also makes an EXCELLENT affordable COMPOST STARTER that has more good bacteria to accelerate your composting projects I LOVE THIS STUFF its awesome

I have had an established twenty gallon long. Aquarium for over six weeks, from time to time, I have been losing guppies like crazy it's been terrible today. I added two 10 ml of this product it perked up my guppies as a matter of fact my dumbo looked like, he was gonna be the next victim. And this helped his colors back day 2 everyones good 👍 buy it It's a probiotic