I approve this product.

The first bottle I recieved had thick liquid and a strong sulfur/rotten egg smell. Amazon sent me a replacement and the liquid was clear and had a light scent. I put 4 cap fulls in my 20 gallon tank after 25% water change because I have had issues with cloudy (milky) water which I suspect is because of bacterial bloom. This stuff worked in less than 16 hours. My water is almost completely clear and my fish seem happier. ðŸŸðŸŸ

Moved across country and needed to get a cycle going quickly to get the fish up and running again. Researched it and found this product. Decided to try it. It was amazing. Came exactly when it was supposed to. In the winter in freezing temps. Comes in a small box. I opened it. Kind of smelled and had that gunky bottom of the aquarium sort of look. I could see it when i measured it and poured it in. Within days my cycle had be started still had to add prime, but ammonia, nitrites went down quickly. Within a week the cycle was going and everything had started up. I used it as it said to the first couple of weeks, but didn't really need it after that. Kept it around for mini crashes, or for just a bit boost. Always worked. Would recommend over and over.

I recommend reading the website FAQs on this product. I ordered this in summer, got it next day, bottle smelled like death! They did replace it the next day. However on the site a smell earthy or stinky does not matter. I added it to tank and water does not stink, change water color, or harm fish!
Important to know that product should be used with a simple chlorine and chloramine remover/water conditioner NOT a ammonia remover. Product should also NOT be used with a growing plant light or UV sterilizer above 20 Watts as this will begin to kill the bacteria in the water. Simply turn your light at an angle for the next 5 days. Use only when you are testing for high total ammonia or Nitrites. This is the fastest and most recommended product on most fish keeping sights and don't let the smell put you off. Company will send you a new one however if you do not trust it.

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!