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Starting The Cycle - Cycling With And Without Fish

Starting The Nitrogen Cycle With Fish
This is not the preferred way to get the nitrogen cycle started because the fish are being exposed to ammonia and nitrites during this process. Many fish can not and will not make it through the cycling process. Often times the fish become stressed and fish disease starts to break out. I wonder what percentage of disease is caused by the cycling of new aquariums?

Certain fish species are hardier than others and seem to tolerate the start-up cycle better than others. For freshwater tanks, the zebra danio is a very hardy fish that many use to get the nitrogen cycle started. For saltwater tanks, some have reported success using damselfish to get the process started. Again, using fish to cycle is not a good idea and you may be throwing your money (on dead fish) out the window. There is a better way. Read on, young grasshopper.

Starting The Nitrogen Cycle Without Fish
There are a few different ways to get this process started. To easily get an ammonia reading from your tank water try the Seachem Ammonia Alert. It sticks inside the tank and has a circle that changes color depending on the ammonia levels in the tank. It doesn't seem to have the most accurate measurement so you would need to get a good liquid ammonia test kit to get a more accurate reading of the ammonia levels in your tank.

Once the cycle has started only add one or two fish at a time. Wait a couple of weeks before adding more fish. This will give your tank the time it needs to catch up with the increased bio-load.

Speeding Up the Cycling Process
There are things you can do to speed along the process of cycling your aquarium.

Author : Mike FishLore

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Nitrogen Cycle Tips / Comments

From: Dave M.
To start the CYCLE, one should never use fish food! Most, if not all, fish food (flake or otherwise) contain heavy amounts of phosphate. Once the Nitrogen Cycle is in it's final stages, the first thing you will notice is an explosion of all types of algae. Phosphates encourage it's growth! Don't tamper with the Ph, till after the Cycle is complete. Afterwards, try to keep the Ph low, around 7.0-7.2, as a high alkaline also increases algae growth. Purchase several (cheap) "Bunched Plants" and place them in the tank. No need to draw them to the bottom; just throw them in, if you like, as you probably won't need or want them anymore after your landscaping plants and the aquarium establishes itself. This method will "out-compete" the algae and your "Planted Tank" will be virtually free of this pesky micro-plant.
Thanks for allowing my input on the Aquarium Cycle.

From: Brandon J.
Never rinse your filter media with regular tap water if it becomes clogged. The chlorine in the tap water will kill your benificial bacteria instantly and you will have to start all over. Then you will see an explosion of ammonia and nitrites. Rinse your filter media in tank water if you must rinse due to over feeding. Always feed no more than yor fish can eat in 2-3 minutes to avoid filter media clogging which can cause over spill and less water going through your bacteria media culture. Good luck!

From: Mike
SeaChem also came out with a product called Stability, which works great to speed up the cycle. I've used Cycle and Stability and I thought Stability worked a little better. I've heard Marineland's Bio Spira is great too but it's hard to find. Marineland's head scientist is an expert in Beneficial Bacteria... so I trust their stuff a lot.

From: Cody
I used the Bio-Spira in my tank only a couple of days after setting it up from scratch and it worked absolutely fantastically. I have not since ever seen a spike in ammonia, nitrites, or nitrates. My tank is now two months old and I was able to add fish in the first few days after setting it up. I highly recommend this product to any new setups.

From: Carsten
In Feb 2007 my brother passed away and his wife could not handle dealing with an aquarium. So, I brought them home 700 miles in a 2 gallon cooler also with his filter, media and sorted stuff. After I got home I needed to setup an Aquarium quickly. I had one when I was younger and know a little. I left them in the cooler with a heater, plants and air stones for 3 days. I monitored the water chemistry since I wanted my brothers fish to live. I saw the ammonia levels rising, etc. So when I visited my local fish shop they recommend I used the bio-spira. Thank God for that stuff, my tank started to cycle quickly, ammonia was there then after a day with Bio-Spira nitrites, then Nitrates kicked in, and ammonia's started down. Worked like a charm and they are all well.

One other experience, I overcleaned my tank, back to the LFS, more Bio-Spira to fix the issue. I've also learned that I never clean the tank and change out the filters at the same time. Another great product I keep on hand is Prime. Dosing with Prime will help get ammonia levels down while the cycle is stabilizing. Setting up a new 55 gallon today and ran across this great site. Thanks for all the efforts.

From: HSimpson - about Septo-Bac
Septo-Bac can be used to speed up tank cycling and it is a fraction of the cost (a box of 12 packages of Septo-Bac costs about $5 and can be used to cycle 10 150 gallon tanks) of more expensive products such as cycle, bio-spira, stability, and stresszyme.

I did not post this to market Septo-Bac and for those who doubt me, you can do a google search about other peoples' experience to use Septo-bac to quickly cycle large tanks. I can honestly tell you that I was able to cycle the 5 gallon hex in 13 days. Normally it can take 30+ days to cycle a tank and the Nitrite phase is supposed to last the longest (usually 14 days, but some people have got stuck in this phase for 20+ days). I believe that the introduction of Septo-Bac into the tank shortened the Nitrite spike so it was almost the same number of days as the Ammonia Spike. 7 days for the ammonia spike vs 6 days for the Nitrite spike.

From: Tom
Hi, I'm thinking about getting a 60 litre tank with 5 tiger barbs and 5 green tiger barbs. How should I go through the nitrogen cycle and when should I add the fish. Thanks. tom

Re-read the options above for getting the cycle started. Once you are getting nitrates and no readings of ammonia nor nitrites you can safely add fish to your newly cycled aquarium.

From: Kelly
I do use the biospira and it works very well.
Thanks for the comment on bio-spira. I've heard many successful reports from hobbyists using this product to start the nitrogen cycle. Thanks for the comment. Mike

From: Dave
I set up my new 55 gallon tank a little over a week ago and at the suggestion of a fellow member of a fish forum tried Bio-Spira to cycle it. After eight days, the tank is done and ready for fish! I strongly recommend this product to anyone confronting the establishment of a new aquarium.

From: Joe - Cycling Aquarium with Fish
The best way to cycle a new tank is "patience". Start off with about five fish and do a 10% water change every other day. Ensure that you add anti-chlorine in the new water or let the water settle for about 2 days to neutralize the chlorine. Once your biological filter is established, add a few more fish and so forth. Also note that when cleaning aquarium decor, use the same water from your tank as the normal tap water will kill all good bacteria. Happy fish keeping and remember to do at least a 20% water change weekly.
Indeed, the old fashioned way of doing the cycle. There are better, quicker more humane ways (fishless) to do it nowadays though. Also, just want to add that letting water sit for 2 days may remove chlorine, but what about chloramine? To our knowledge, you still need a water additive to remove or neutralize chloramine.

From: Mike - Read Up on the Aquarium Cycle
Okay, I read this too late... Bought and set up a 20 gallon tank, let it sit for 4 days with filter running. Then added 6 guppies, 6 neon tetras, 2 swordtails, 2 panda corys and 2 Danios. Over the course of 3 days. Lost a few guppies and one tetra on days 8 and 9. Could this be related to the cycle that I was ignorant about?
Mmm, most likely because the cycle is kicking in gear with the build of ammonia and nitrites which can be very harmful to fish. That's a lot of fish to add all at once. Ideally, you want to add a couple at a time to avoid taxing the cycle. Adding a few at a time allows the beneficial bacteria time to catch up to the increased bio-loads being introduced into the tank. I know it can be very difficult to exercise patience, but that really is the best advice when going through the cycle and stocking a new fish tank.

From: Cassie - Confused about the cycle
I'm so confused! I have a 5 gallon U.S. tank and I've been using it for like a year. I just cleaned everything out using tap water putting everything back in to start fresh because my fish died. I'm doing a lot of research so I can get everything right but I'm not sure what to do about the nitrogen cycle. Could you please tell me in steps what to do!
Hmm, ok. I'll try to break it down into steps:
  • Fill tank with dechlorinated tap water or pre-mixed saltwater for saltwater aquarium keepers.
  • Determine your method of starting the cycle. Fishless is the quickest and most humane way. For freshwater tanks, get some Bio-spira and add it to the tank. For saltwater tanks, live rock is the way to go. As the rock cures in the tank it will cycle your tank.
  • Test the aquarium water with your test kits for ammonia, nitrite and nitrates.
  • Once you start getting nitrates and no nitrites you can safely add fish. If you're using live rock in saltwater tanks you may not see any of these (ammonia, nitrite and nitrate). If you've had the rock in the tank for several weeks/months you can assume that it's safe to slowly begin stocking the tank.
  • That's it!

From: Cory - Cleaning tank during cycle
Another common problem in the cycle stage is people over clean their tanks during partial water changes and maintenance. If you use the food or fish starting methods, its very important not to disturb the media bedding to allow beneficial bacteria cultivation and growth. Media is the largest source for this growth and over cleaning in the first few weeks can diminish this cultivation causing an elevation of ammonia and/or nitrites.

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