Fritz Aquatics FritzZyme 7 Live Nitrifying Bacteria Naturally Removes Amonia & Nitrite for Freshwater Fish (16-Ounce)

This stuff always works for me, especially if I have light stock in my tank. I do fish in cycles all the time and never had any issues with fish dying on me thanks to this product. You could prevent ammonia, nitrite, and nitrate spikes by adding like 4-5 small fish to your aquarium. Don’t add too many fish! More fish means more waste, which your new system won’t be able to handle. Add easy aquarium plants (Hornwort, Salvania minima, Brazilian Pennywort) as many as you can. You need plants plus this product for a successful fish in cycle!

When I first set up my aquarium, I started with Seachem Stability. However, after 2 weeks, my nitrite levels still hadn’t reached zero. I decided to switch to FritzZyme because it contains live nitrifying bacteria. After I started using it, my tank finished cycling during the third week. I honestly wish I had started my aquarium with FritzZyme from the beginning. If you’re looking for a product to help establish the nitrite cycle in a new tank, I highly recommend this one. Just make sure to follow the dosing instructions on the bottle for the best results. And ease of use.

This is my first time using this product. The reviews spoke highly of this company. I started with ghost feeding the first week, but wasn't getting as much ammonia as I wanted to begin the cycle. I got the ammonia that goes along with this bacteria in a bottle. Got the ammonia up to 4ppm 2 nights ago. Yesterday, this bottle came in, and I dosed it as recommended. This morning I did my tank parameter testing with the API Master Kit. In my cycling tank it read 2.0ppm ammonia, 0 nitrites, and 5.0ppm nitrates! It just skipped right over nitrites! That tells me this product is VERY effective! Considering it's taken me months to cycle other tanks, this is mind blowing to me. I'm glad I listened to experienced folks that using high quality ammonia and live nitrifying bacteria is FAR superior to ghost feeding. I purchased the smallest bottles they have, and I'll still have nearly all of it! Well, I guess that means I'm just going to have to get more aquariums, ha! It's so easy I'm still processing this. Don't sleep on these products, the value far exceeds their price! I'm also glad this can be used as a maintenance for established tanks. It will be a great product to have on hand to maintain a well functioning cycle.

My concern were the reviews that said it had “ammonia”. However, most tap water has ammonia, mine does. So I cannot test this product using tap water. Or else it would give a false positive result. Also, the smell of “rotten eggs” is a byproduct of bacteria “sulfur” - so it’s normal to smell this. For the test. I used a sample of water from an established tank that already has 0 ammonia and added FritzZyme 7 to it. Using the API ammonia liquid test, results are FritzZyme 7 does NOT contain ammonia. Looking forward to how this works on my tanks that need a fortification of BB. UPDATE: 1 week later, decided to use it on a newer tank to test its full potential and it cycled (day 1: 5/28/25 and today 6/3 final results)! Amazing! Tip, if doing IN-Fish cycle, make sure to watch any spikes in ammonia, nitrite, nirate, or PH daily. If needed do small WC, don’t mess with the substrate or filter when doing so, and let the cycle do its thing to keep your fish safe. Trust the process. This product did what it said it would do. Using it now to fortify my other tanks.

So much contradictory and bad information out there. Here's what I could conclude that seem consistent from various sources. The parasites are thought to be released in the water column at night. I read this after a stubborn case that was responding slowly. I changed application to evening and things were cleared up in two days. I did 24 hr interval, 30% water change, per instructions. I did it in evening. I raised temp from 76 to 79, I did not want to stress fish and plants at 86 F, sheesh. I continued for 3 days after last spots disappeared. 9 day total treatment time. I poured a dose in a white bucket and let it sit for 24 hrs. At first, water was bright blue. After 12-14 hrs it was nearly clear. Many sources claim light sensitivity. Perhaps another reason to apply at night when strength will be full and parasites are free swimming. NOTE: I don't think you can use this with Prime. Instructions say DO NOT USE WITH SULFUR OR SULFINATE BASED CONDITIONERS. Take a whiff of Prime. Smell that rotten egg? Ya. I used API water conditioner. Good luck trying to find ingredients of fish chemicals. Very frustrating (bad bad manufacturers!). It WILL definitely stain your air lines etc. I read aquarium coops blog on this, they claim to have never seen a problem. No idea how, unless they simply do not have PVC or silicon tubing. At end of treatment, mine are bright blue. I added some salt. I did 4 gallon changes based on actual water volume (not tank size) and added half teaspoon. Just enough to deal with nitrites in case of disruption of bacteria. The ich-x is claimed by some to have mild antibiotic effect. As an aside, my fish like salt. If I didn't have sensitive plants, I'd add it all the time. It prevents scale build up on tank, my fish thrive, etc. You don't need as much as they say. Salt is good. Really. I am trying to find a minimum that doesn't impact plants. Fish and plants seem ok, not 100% sure about shrimp and snails, they seem less active. I don't like the long duration required as this stuff is very toxic, however, it works.

I tried two other products and followed results with an API master test kit. I started a freshwater 55gal tank and began a fishless cycle (with API tap water conditioner), however I wanted to speed up the process with a starter product. I first tried Petco's Imagitarium Biological Booster product at the recommended starter dose. After one week using Dr. Tim's ammonia to start the cycle I was at 2ppm ammonia, 0ppm nitrite and 0ppm nitrate. I tried a second starter dose, again after a week (now 2 total weeks in) I was at 2ppm ammonia, still 0ppm nitrite and 0ppm nitrate. Second, I tried API's Quick Start product at the beginning of week 3. At the end of week 3, you guessed it, 2ppm ammonia, 0ppm nitrite, 0ppm nitrate. I did not attempt a second dose of API Quick Start. I was beginning to lose faith in the idea of "quick start products". After being frustrated by the previous two, I gave FritzZyme 7 a shot based on positive YouTube review content. I added the full 16oz bottle to my 55gal tank. The very next day I began to see trace nitrite readings (well under .25, most likely .125 or so). Within two days after that I saw ammonia begin to recede, and nitrite to continue to rise by about .125 daily until it hit .5ppm nitrite by the end of day 4. By the end of the week (now 4 total weeks in) I have 0ppm ammonia, barely traceable amount of nitrite and 5-7.5ppm of nitrate! This product works, and works fast. It is no more expensive than the others at the box stores. Don't waste your money on those, buy this and get a cycled tank faster!

This was effective for me. I did a fish-in cycle, used some lightly seeded media and gravel from another tank and then used this bacteria and dosed with Prime everyday for a few weeks. The cycle was finished pretty quick, taking about three weeks rather than the normal six or so, and I didn’t loose any fish and they all looked healthy and happy throughout. I tested my parameters regularly and had only mild spikes in levels before it colonized. I was always skeptical of bottled bacteria but this one seems to work quite well.

I always use when I clean filters.

Brilliant

I emailed Fritz about some quries and their response was prompt and friendly. been using these for tanks and i do not need to add any salts or whatever. Fzz7 will stink like old eggs and a bit brownish but it is normal, not spoiled. Fritzguard is bluish and dun need it as much as Fzz7. Keep them normally in cabinet and use them every water change. Instructions are clear..

El producto llegó caducado.

I tried quite a no of other bacteria for my fish tank and found this to be the most effective. Only a small amount is needed for a stabilised tank.

Al parecer este producto es muy bueno y cumple con lo que se describe en la página y en las revisiones que se hacen de él, sin embargo lastimosamente llegó a mi casa con la fecha de caducidad expirada hace un año. Si se vuelve a plublicar, seguro lo compro.