My CYCLING experience....


For all those researching cycling, I figured I would share my cycling experience...

36 gallon tank with new HOB filter, new gravel, new ornaments

After extensive research, forum reading, and the fact that I have a degree in Environmental Engineering and work in the field of waste water engineering, I jumped at the idea of doing a fishless cycle. Went an bought a 10% solution of ammonia from Ace and was ready.

Day 1- After 24 hours of tank setup and running (with water conditioner), I decided to spike in 5mL of ammonia, instructed dosgae of stability. Using API Master Test kit, my ammonia appeared to be 5ppm, nitrite & nitrate 0ppm, pH 7.8. (all parameters were 0ppm before spike)

Day 3- Being the impatient person I am and wanting something to happen, after 48 hours of no changes in any readings, I decided that maybe my spike was too high, so I did a 5 gallon water change using prime and added my 3rd dose of stability. Ammonia appeared to drop a hair to around 4ppm.

Day 5- During this time I never added more ammonia since I was still measuring ammonia from the very first dose. I did however, continue daily stability as directed. After another 48 hours and still nothing changing (no reduction in ammonia, no nitrite or nitrate) I decided to dump in a bottle of Tetra Safe Start (rated for 40 gallons) discontinued Stability at this time.

Day 6
- After 24 hours of the Tetra Safe Start and not a hair of change in my readings, I decided to do another 10 gallon water change with prime to try and reduce the ammonia a little bit (down to 3.5 or so). I also dumped in a bottle of Dr. Tim's One & Only hoping that anything would help jump start this cycle as I had family coming into town in the near future and wanted fish in my tank.

Day 8- After another 48 hours of absolutely no changes in any readings, I went up to the LFS and nabbed some of their gravel, put it in women's hose, and dropped one bag in my filter and the other in the bottom of my tank. However, their gravel was extremely clean and I don't think this did anything for me. I also added a 2nd heater and cranked up the temperature to about 85F.

Day 9- no reduction in ammonia (still 3.5), no nitrite, but nitrate (was approx 5-10). For a brief second I got excited thinking my cycle was finally working, but then remembered the small addition of water that was added to the tank when adding the gravel from the LFS, which I believe accounted for the increase in nitrates.

Day 11- After another 48 hours of no changes and becoming frustrated that nothing was happening, I went to LFS and discussed my problem. My LFS is a locally owned small aquatics store that is super awesome with a huge assortment of freshwater and saltwater stuff. They even harvest corals for saltwater aquariums. So in short, I tend to trust these people for advice. The guy I talked to told me that he had tried fishless cycling before and found it pretty difficult, but if I was determined to continue, which I was, he had heard decent examples of Bio-Spira working well for people doing a fish-in cycle. With family coming into town in a week, I decided to give it a shot and added the bag of Bio-Spira.

Day 14- After literally trying all 4 of the major bottle bacteria on the market (TetraSafeStart, Stability, One&Only, and Bio-Spira) and still absolutely no changes in any of my readings I decided the heck with this. I did roughly a 70% water change and added prime. With the ammonia down to 0.5ppm, I was going to give a couple of days to see if anything would happen before I just went and bought some fish. Maybe the mass combination of bacteria got in the way of each other or maybe not, since they were "kind of" spread out. Who knows.... Discontinued 2nd heater at this time to let temperature come back down to around 77F.

Day 15- Added new HOB filter (Fluval C4), cut apart previous cartridge and put the "sponge" media (with whatever bacteria had accumulated, if any) in front of the sponge media of the C4. The Quietflow30 that came with tank was bypassing too much water and I wanted to upgrade to something that had more space to personalize media. Decided to go ahead and do this now rather than waiting a month. Nothing else was done on this day, except of course my daily readings.

Day 16- With still nothing happening, I did another 15 gallon water change with prime and added 6 tetras to cut my losses and finally have something to look at while I performed my cycle. After adding fish readings were as followed: Ammonia was reading approx 0.25ppm, 0 nitrite, & slightly under 5ppm nitrate

Day 24 - Fast forwarding a few days, my ammonia has been steady at 0.25ppm. I have never seen the slightest trace of nitrites, however, I am increasing in nitrates (10ppm). I have tested my water every single day to track any changes. I am guessing that for some reason with all the bacteria combinations, I was able to basically skip the nitrite spike portion of the the cycle, but am going to continue on the path I am for at least another 2 weeks before I add anymore fish. Also, because I already had the bottle, I am using stability daily as directed since I added the tetras. This is the only chemical I am using at the moment. I will add prime during water changes if needed. Also worthy of noting (during Days 16-21), ZeoCarb media was in my filter to aide in the removal of ammonia, but I decided to remove this on Day 21. Since adding fish (8 days) and typically feeding 3 times a day (small amount, they eat it in about a minute or so) my ammonia has not decreased nor increased from 0.25ppm. I believe this has to do with the combination of stability, zeo-carb, and previous bacteria dosages.

So that's my story and where I am now. In short, I kind of just wish I had bought the tetras from the beginning and used prime and stability to help them. I personally believe that the small trace of ammonia I am seeing now has to do with trace amounts of the "pure ammonia" from the store bought bottle not being broken down by the beneficial bacteria, but who knows. I am going to continue monitoring daily and enjoy watching these fish. My current plan is to wait until nitrates are actually up closer to 20 or 40 ppm, do a water change (with prime), and hope my ammonia actually drops to around 0ppm. I'll then continue monitoring daily until I am absolutely convinced everything is cycled properly and add some more fish. Not having any other tanks to enjoy, there is no way I would be able to fishless cycle for 3-4 weeks with nothing to look at. Fish-in cycles can be done safely, and allow you to actually enjoy the expensive equipment you just purchased!!!

Sorry for the long post, but I'm sure someone out there preparing to cycle might find this helpful. BTW, joining fish lore has been awesome and extremely helpful!

After 5 more days of trace ammonia, 0 nitrites, and now up to almost 40ppm nitrates, I decided to do a couple of water changes and retest my conditioned tap water. After multiple tests, I found that my ammonia readings were not providing a true 0 reading. All of my tap readings were a faint green (~.25ppm). With this knowledge and the increasing nitrates I am comfortable that my tank has cycled. The tetras are all doing well, the biggest one is obviously the leader as he can get a bit nippy at times. With all the buildup of "junk" in my gravel (probably from all the bottles of bacteria I dumped in) I went to the local fish store to pick up a few catfish. Brought home 5 albino corys (they are super small). I also couldn't pass up on two young Electric Blue Acara's that were on sale. They are barely bigger than my tetras right now and I am excited to watch them grow! Everyone seems at ease as of now. The tetras were very interested in their new tank mates! I plan to monitor nitrogen cycle closely as I realize I just added 7 new fish, but the cory's are so little I can't imagine their bio-load really adding to much of a shock to the tank.


Way too much, too fast. Fishless cycling is a slower process. I'm an impatient person too, and I always fish-in cycle with no problems. Goes faster and you actually get to do something other than stare at a box of water for weeks.



Oh my, what a journey you just completed. I am happy to read that you have finally had a happy ending.

I have read a lot about folks on here having good luck with the bacteria additives and that is great but personally I prefer doing it the harder way and go with a fish in cycle. It is a lot of work having to do so many water changes (every other day) but once it is done, it's done. I started from scratch with a fish in cycle, December 18th and the cycle was complete January 19th. I love the fact that I was able to enjoy watching the fish in the tank during the whole month it took to cycle it and I am happy to say, I didn't lose a single fish during the cycling process. Starting with hardy fish is a must for a fish in cycle.

I have read on here too from several folks that they never had a nitrite spike either when using the BB in a bottle. Mine went off the chart just before the cycle completed. I had to do water changes every day for 4 days in a row during that time. On the 5th day my tank was cycled.


Patience is definitely key. I'm on my 10th day of a fishlless cycle. I dosed my ammonia to about 4ppm no change in a ammonia until the 7th day. Ammonia had dropped to about. 50ppm and my nitrites spiked. My ammonia now will drop to 0ppm by the afternoon after dosing with ammonia back to 4ppm. My nitrites are still spiked. Which I read is normal and sometimes takes longer to drop. Good luck

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One thing I will add is after you use TSS you are suppose to wait a while to do testing really, because it can make your test results go a little wonky. It sounds like you had quite the journey with cycling, and it sounds like you are pretty close to completing it.

I personally prefer fishless cycling with just pure ammonia. It may be slower compared to fish-in cycling, I wouldn't really know, but I just feel bad for the fish. My five gallon took a little over two weeks to cycle using only pure ammonia (no bacteria starter).

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