Starting cycle

The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.


Aquarium Advice Apprentice
Oct 21, 2023
I am about to start a new saltwater aquarium with Fritz turbo start 900, in the directions is says to add livestock or their fritz fishless fuel. Is this necessary for finishing the cycle? The directions are quite confusing and I’m not sure wether or not if I can just add the turbostart and wait till my ANN levels are low enough to add livestock. Also, when my cycle is finished can I add multiple fish and corals at once or do I need to add them slowly?
To cycle a tank you need to grow the microbes that consume ammonia, with no ammonia on the aquarium those microbes won't grow. A fish in cycle requires there to be fish in the aquarium for that ammonia source. For a fishless cycle you need to artificially dose ammonia over a period of time, and thats normally done with ammonium chloride, thats what the fishless fuel is. You can also use fish food as an ammonia source, but its tricky to get the right amount of food in the water. A cocktail shrimp can also be used.

Simply adding the fritz turbo start on its own wont cycle a tank as there wouldnt be any food for the microbes to feed on and multiply. The microbes will starve and die. There might be some ammonia come out of your live rock or substrate to start with, but not enough to cycle a tank.
So how long should I wait to add fish after Fritz turbo start? Would a pair of clownfish be a good amount?
Im not really a saltwater person, but the principle of cycling is the same as for freshwater.

For a fish in cycle you want 1 small fish for every 10g of water to start with. You can add fish straight away. Then test your water daily and be prepared to do regular water changes until the tank cycles, which could take several weeks. Potentially daily water changes.

While fritz have a good reputation for their bacterial booster products, they dont always work and they may not help with your cycle at all. They are live products that can be dead before you took it out of the store. Dont expect it to cycle your tank overnight.
So how long should I wait to add fish after Fritz turbo start? Would a pair of clownfish be a good amount?

Here is the page for the Turbo900. The directions are pretty clear. Follow them and you can have a cycled tank in as little as 5 days. ( ) The print is bigger than the bottle so might be easier for you to read. (y)

With all that said, you have to understand that the "cycle" ( a.k.a. creating the biological filter) is the creating of the microbes that convert ammonia into nitrites and the microbes that convert the nitrites to nitrates. TurboStart900 contains these 2 microbes so you don't have to wait for them to develop naturally. ( This is now the biological filter.) You have to think of the biological filter as a living breathing organism that grows and shrinks based on the amount of ammonia and nitrites available in the tank. So say you add enough of the TurboStart that adds enough microbes to convert 5ppm of ammonia in under 24 hours but you only have fish that produce 2 ppm of ammonia in 24 hours, there will be some die off of the microbes until it reaches a level where enough microbes are present to consume that 2ppm of ammonia.
Conversely, if you add enough TurboStart to reduce 2 ppm of ammonia in 24 hours but your fish load produces 5 ppm of ammonia in 24 hours, the biological filter now needs to grow in order to match the ammonia production. The good news is that these microbes reproduce rather quickly but we are talking hours to days but not weeks so you have to be aware of the ammonia level at the start so that if the ammonia level does rise to a toxic level to the fish, you can address that issue with either a water change or a water conditioner like Seachem's PRIME or adding more of the TurboStart. Unfortunately, there is no way of knowing how many microbes you are actually adding to the tank other than by testing the ammonia level. :(

If you are concerned about the product, you can add it to the tank then add enough ammonia to the tank to a level of 2 PPM and see how long it takes to go back to zero before you add your fish. If your ammonia and nitrite levels go back to zero in under 24 hours, that would show you have an active biological filter and it's safe to start adding your fish.
Take note that the TurboStart should be coming from a refrigerator so buying it online could be dicey as it will not be refrigerated for the duration of it's delivery. This could greatly hinder the effectiveness of the product as the microbes could be dieing off in the bottle. It also has a short shelf life ( 4 months) so you really want to check it's expiration date and not get a bottle that is close to it's expiration date. :whistle: Truthfully, if you are only talking about adding a couple of smaller fish at the start, I would consider using the Fritzyme #9 instead since it doesn't need to be refrigerated and has a longer shelf life because it is less concentrated. The same applies to the expiration date and checking ammonia levels at the start.

Hope this helps. (y)
Top Bottom