

🐠 Transform your aquarium’s health with the power of live bacteria—don’t let your fish miss out!
FritzZyme 7 delivers live, species-specific nitrifying bacteria that rapidly eliminate toxic ammonia and nitrite in freshwater and brackish aquariums. With over 30 years of industry leadership, this easy-to-use, no-refrigeration formula accelerates biofilter cycling and maintains aquatic stability, ensuring a healthier environment for your fish with less wait and worry.
















| Brand | Fritz Aquatics |
| Customer Reviews | 4.6 out of 5 stars 3,338 Reviews |
| Item Form | Liquid |
| Item Weight | 0.3 Ounces |
| Liquid Volume | 32 Fluid Ounces |
| Manufacturer | Fritz Aquatics |
| UPC | 080531802106 |
R**L
I'm impressed! Don't wait on getting this product!
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.
A**J
Quick source of beneficial bacteria.
Having trouble starting or completing the nitrogen cycle in your aquarium? Need more beneficial bacteria? Use this product, in a heavy dose. IT WORKS !
D**L
Contains no ammonia / UPDATE
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.
S**Y
Yes!
This product at the time I purchased is valid and effective. I started a cycle for an African Dwarf Frog and had immense success. These creatures are unknown with contradictions all over the internet. They're exceptional with sensitivity that requires work. I can attest that this product worked for me when I accompanied it with a seeded sponge filter fron an established aquarium
J**S
Helped To Cycle My New Tank More Quickly
I replaced the substrate and planted in my established aquarium. I've owned fish for over 30 years and always just let the tank sit for about 2 weeks and cycle naturally before adding the fish back. I decided to try this product to speed up the process so that I could my fish back from their small holding tank back to the main tank as soon as possible. I was a little hesitant adding it as the solution smells terrible, but it is live bacteria! I checked the ammonia and nitrites after a few days and they seems almost where they should be, so I added the fish back. They were a little sluggish at first, but were eating and back to normal with a week. Overall, the best way to cycle a tank is still waiting...
C**Y
Fish approved
This stuff workssssss. Was having ammonia issues in the late stage of cycling and this fixed it all up in a couple days. I can’t recommend this enough. Note, watch the amount you buy because it expires. All my fish are happy campers with the ammonia being taken care of and it’s a good investment.
J**M
Works well for our freshwater fish
We like using this product. We've bought it several times in the past few years for our freshwater fish.
T**N
Amazing product
I bought this product after seeing multiple reviews outside of Amazon saying that this product worked very well to start an aquarium with fish instantly. I confirm it works this way!! I had an emergency to relocate 10 white cloud mountain minnows cramped in a 5 gallons who were fighting too much. So I bought a 10 gallons and filled it with remineralized RO water, I did not even had a filter for this new tank, so I tossed a filter sponge, a bit of drift wood and a USB water pump just like that. Then I poured the recommended dose for a new 10 gallons tank and I did no see any alarming ammonia or nitrite spike, only once in 2 weeks had I have to change the water due to a minor spike and it has been a month now that the 10 gallon is up a running (with a filter, substrate and plants now). I did not lose a single fish. I highly recommend this product.
Trustpilot
2 days ago
2 weeks ago