Fishy Cycling my 75 gallon
- Thread starter Letsgometsreyes
- Start date
“Cycling A Tank”
What we mean by this term, is the process of establishing an environment that will beneficially support fish life, with minimal stress to the fish and to you. The terms used here are relevant to the “nitrogen” cycle and how it relates to the aquarium.
The first item for discussion is Ammonia (NH3). All decaying matter, like uneaten food and from fish wastes, produces this. Any detectable amount is trouble for your fish, and levels of .25 ppm and above can damage fish permanently, based on length of exposure. This damage occurs to the gills, and causes breathing problems. It will damage the gills whether the fish live or die.
Secondly, the bacteria that break down ammonia produce Nitrite (NO2). This nitrite blocks the ability of blood to absorb oxygen. Even if the fish can breathe, they are not able to utilize the oxygen they take in, as easily. They can act as if panic-stricken and/or have little control over their movements. Even with short-term exposure at high levels, stress occurs and they may not be able to ward off other immune system attacks.
And finally, second bacteria forms that consume nitrite and forms Nitrate (NO3). While short-term exposure to low levels of Nitrate are not a concern, they can be if too high over a long term. Nitrates are removed with consistent regular water changes or by aquatic plant life.
A cycle is never really complete. It is established and an ongoing evolution. Keeping this “cycle” balanced and continuous is the goal of properly maintaining a tank for a healthy environment for your fish. Strive for Zero Ammonia, Zero Nitrite, and approximately 20 ppm Nitrate or less.
Ways To Cycle Your Tank
I have broken them down into three currently widely accepted methods.
(1) Using Established Bio-Logical Filter Media
This is probably the most preferred and least stressful method that will allow you to stock your fish quickly and depending on the extreme you use, to full tank load.
If you have established tanks already, without any issues, you can put filter media in them before the new set up is ready. The biological bacteria can establish themselves on it and it can be transferred to the new tank and fish added. This can be as simple as sponges on filter intakes, filter cartridges in HOB/HOT, or media in canisters. It can include substrate or décor from other tanks, such as rocks and plants.
Please ensure the tank you are drawing from, has Zero Ammonia, Zero Nitrites and less than 20-30 ppm Nitrates. It should also be a tank free of disease. Do not take media or filter squeezing from tanks you are not sure of or from a local LFS. You could be establishing your new tank with all kinds of problems. Since most bacteria will not be free floating in the water column, taking just the water will not accomplish much.
The bacteria that maintain the cycle need to be fed in order to maintain. Waiting a few days can be disastrous. If moving a tank, keep the media wet in the old tank water, aerated and for the short term only.
This method provides minimal stress to the fish, minimal work on your part, quick stocking, at or near full capacity. But you must plan ahead. It could take several weeks to establish a bacterial colony of sufficient size, on the media you move to the new tank.
(2) Fishless Cycling
Just as it sounds, you can establish the cycling environment without any fish. This method does not pose any threat to fish, establishes a large bacteria colony allowing full stocking upon completion and gives you time to decide on what fish you want.
When establishing a tank with this method, you will use a source of ammonia to initiate the nitrogen cycle. After your tank is set up, add water and treat for chlorine/chloramines. Your filtering systems and heaters should be in place and operating to your satisfaction.
Add ammonia to bring the tank to a concentration of 5 ppm. The amount you add will vary with the size tank you have. Do not be in a rush. Add small amounts and test, repeating as necessary. If you get it too high, you can drain and refill.
Now the hurry up and wait part happens. Every two days, test your ammonia level in the tank. When the ammonia levels start dropping, add additional ammonia as required to keep the ammonia at 3-4 ppm, start daily testing and test for ammonia and nitrites. Nitrites should be developing as ammonia goes away. This first stage could take 1-3 weeks.
When you see the test results showing Nitrites, start maintaining your ammonia at the 2-3 ppm range. The nitrites increasing reflect you are in to the second stage. Continue daily testing for ammonia and maintain the tank in the 3 ppm range. You will see nitrites climb so high they will be off the scale for a reading. This will continue for one to two weeks and it will seem the nitrites are never going to go away.
There will be a day where you test and the nitrites have completely disappeared, thus, the bacteria that convert them to nitrates have established themselves. When you see this drop to zero on nitrites, dose ammonia in the tank to about 5 ppm, and wait 24 hours. If at the end of that period, ammonia and nitrites are zero, your cycle has been established. Test for nitrates, and do a 75-90% water change. Pull your water down to 20 ppm nitrates and add the fish! If you have to wait to get your fish, keep the cycle established by dosing more ammonia, but you may have to do another water change before adding your fish.
(3) Fishy Cycling
This method is probably what many fall into from all the myths that run rampant out there. It is also the method that can cause severe stress or death to the fish. There are some simple techniques that make this type of cycle go easier, but take some pre-planning on your part.
The basics of this method are to set up your tank, fill, treat with a water conditioner, add some hardy fish that can handle stressful conditions, test/monitor the ammonia and nitrite levels, and do water changes as necessary.
When your cycle is established, you have a bacteria load that can handle the fish that are in there presently. More fish can be added in small numbers over a period of time, allowing for a mini-cycle to grow the bacteria levels to the new bio-load. You need to pay constant attention to your tank, testing daily, doing water changes when required, not when you can get around to it. Do not assume that you can add more fish just because reading are undetectable or low. Give the environment time to respond.
You will be captive to testing at least twice daily, doing water changes whenever ammonia or nitrites hit .25 ppm. Do not be surprised that even with a cautious approach, you lose some fish.
What we mean by this term, is the process of establishing an environment that will beneficially support fish life, with minimal stress to the fish and to you. The terms used here are relevant to the “nitrogen” cycle and how it relates to the aquarium.
The first item for discussion is Ammonia (NH3). All decaying matter, like uneaten food and from fish wastes, produces this. Any detectable amount is trouble for your fish, and levels of .25 ppm and above can damage fish permanently, based on length of exposure. This damage occurs to the gills, and causes breathing problems. It will damage the gills whether the fish live or die.
Secondly, the bacteria that break down ammonia produce Nitrite (NO2). This nitrite blocks the ability of blood to absorb oxygen. Even if the fish can breathe, they are not able to utilize the oxygen they take in, as easily. They can act as if panic-stricken and/or have little control over their movements. Even with short-term exposure at high levels, stress occurs and they may not be able to ward off other immune system attacks.
And finally, second bacteria forms that consume nitrite and forms Nitrate (NO3). While short-term exposure to low levels of Nitrate are not a concern, they can be if too high over a long term. Nitrates are removed with consistent regular water changes or by aquatic plant life.
A cycle is never really complete. It is established and an ongoing evolution. Keeping this “cycle” balanced and continuous is the goal of properly maintaining a tank for a healthy environment for your fish. Strive for Zero Ammonia, Zero Nitrite, and approximately 20 ppm Nitrate or less.
Ways To Cycle Your Tank
I have broken them down into three currently widely accepted methods.
(1) Using Established Bio-Logical Filter Media
This is probably the most preferred and least stressful method that will allow you to stock your fish quickly and depending on the extreme you use, to full tank load.
If you have established tanks already, without any issues, you can put filter media in them before the new set up is ready. The biological bacteria can establish themselves on it and it can be transferred to the new tank and fish added. This can be as simple as sponges on filter intakes, filter cartridges in HOB/HOT, or media in canisters. It can include substrate or décor from other tanks, such as rocks and plants.
Please ensure the tank you are drawing from, has Zero Ammonia, Zero Nitrites and less than 20-30 ppm Nitrates. It should also be a tank free of disease. Do not take media or filter squeezing from tanks you are not sure of or from a local LFS. You could be establishing your new tank with all kinds of problems. Since most bacteria will not be free floating in the water column, taking just the water will not accomplish much.
The bacteria that maintain the cycle need to be fed in order to maintain. Waiting a few days can be disastrous. If moving a tank, keep the media wet in the old tank water, aerated and for the short term only.
This method provides minimal stress to the fish, minimal work on your part, quick stocking, at or near full capacity. But you must plan ahead. It could take several weeks to establish a bacterial colony of sufficient size, on the media you move to the new tank.
(2) Fishless Cycling
Just as it sounds, you can establish the cycling environment without any fish. This method does not pose any threat to fish, establishes a large bacteria colony allowing full stocking upon completion and gives you time to decide on what fish you want.
When establishing a tank with this method, you will use a source of ammonia to initiate the nitrogen cycle. After your tank is set up, add water and treat for chlorine/chloramines. Your filtering systems and heaters should be in place and operating to your satisfaction.
Add ammonia to bring the tank to a concentration of 5 ppm. The amount you add will vary with the size tank you have. Do not be in a rush. Add small amounts and test, repeating as necessary. If you get it too high, you can drain and refill.
Now the hurry up and wait part happens. Every two days, test your ammonia level in the tank. When the ammonia levels start dropping, add additional ammonia as required to keep the ammonia at 3-4 ppm, start daily testing and test for ammonia and nitrites. Nitrites should be developing as ammonia goes away. This first stage could take 1-3 weeks.
When you see the test results showing Nitrites, start maintaining your ammonia at the 2-3 ppm range. The nitrites increasing reflect you are in to the second stage. Continue daily testing for ammonia and maintain the tank in the 3 ppm range. You will see nitrites climb so high they will be off the scale for a reading. This will continue for one to two weeks and it will seem the nitrites are never going to go away.
There will be a day where you test and the nitrites have completely disappeared, thus, the bacteria that convert them to nitrates have established themselves. When you see this drop to zero on nitrites, dose ammonia in the tank to about 5 ppm, and wait 24 hours. If at the end of that period, ammonia and nitrites are zero, your cycle has been established. Test for nitrates, and do a 75-90% water change. Pull your water down to 20 ppm nitrates and add the fish! If you have to wait to get your fish, keep the cycle established by dosing more ammonia, but you may have to do another water change before adding your fish.
(3) Fishy Cycling
This method is probably what many fall into from all the myths that run rampant out there. It is also the method that can cause severe stress or death to the fish. There are some simple techniques that make this type of cycle go easier, but take some pre-planning on your part.
The basics of this method are to set up your tank, fill, treat with a water conditioner, add some hardy fish that can handle stressful conditions, test/monitor the ammonia and nitrite levels, and do water changes as necessary.
When your cycle is established, you have a bacteria load that can handle the fish that are in there presently. More fish can be added in small numbers over a period of time, allowing for a mini-cycle to grow the bacteria levels to the new bio-load. You need to pay constant attention to your tank, testing daily, doing water changes when required, not when you can get around to it. Do not assume that you can add more fish just because reading are undetectable or low. Give the environment time to respond.
You will be captive to testing at least twice daily, doing water changes whenever ammonia or nitrites hit .25 ppm. Do not be surprised that even with a cautious approach, you lose some fish.
Guppies. Better yet, guppy fry that are old enough to eat flakes (albeit, ground up into small bits). Or, young Danios, or similar fish. As they grow, they increase the bioload.
I've always used a fishy cycle. I've always managed to find somebody who was willing to donate a starter colony of "filter gunk" to speed things up. jm1212 has got it right...the ammonia just doesn't have a chance to build up to a dangerous level with a small bioload in a big tank.
He's also got it right on it being a "mini" cycle, as the bacteria do catch up before things get out of hand.
One downside is that if you're looking out for the health of the fish doing the cycling (which you should be), this method takes a long time. Another downside is that a few small fish that one uses only establish a cycle for only those few small fish, not a larger number of bigger ones. You just have to slowly increase the bioload, slowly but surely, over the course of many weeks.
I've got loads of other things to occupy my time (like 4 kids and a crazy job), so I don't mind having a new tank understocked for a long time, and the kids don't seem to mind watching the little fish grow up while waiting for the right conditions to add more livestock.
v/r, N-A
I've always used a fishy cycle. I've always managed to find somebody who was willing to donate a starter colony of "filter gunk" to speed things up. jm1212 has got it right...the ammonia just doesn't have a chance to build up to a dangerous level with a small bioload in a big tank.
He's also got it right on it being a "mini" cycle, as the bacteria do catch up before things get out of hand.
One downside is that if you're looking out for the health of the fish doing the cycling (which you should be), this method takes a long time. Another downside is that a few small fish that one uses only establish a cycle for only those few small fish, not a larger number of bigger ones. You just have to slowly increase the bioload, slowly but surely, over the course of many weeks.
I've got loads of other things to occupy my time (like 4 kids and a crazy job), so I don't mind having a new tank understocked for a long time, and the kids don't seem to mind watching the little fish grow up while waiting for the right conditions to add more livestock.
v/r, N-A
Last edited:
Are you talking to karna68 or me. I was going to do the fishy cycle but changed my mind and Im gonna do the fishless cycling. I will be using sand as substrate which I plan on buying tomorrow. I still have some shopping to do,I already have the amonia that I got from my Job, Im gonna use bio-spera to help with the cycling and Im gonna use Ap master test kit. Ive decided that after cycling Im gonna get some lake malawi cichlids. So now that Ive decided I guess all I have to ask for is some good luck. If i have any questions I'll come right back here. Thanx to all for the replys and suggestions!!!Native American said:
Just offering up my experience with this to enhance other people's bag of tricks. There's loads of good info on this forum.
Next time, I might try my hand at fishless just to see if I can.
I agree...if you want to get the tank going more quickly, fishless is the way to go. Even though I like the fishy cycle, properly done, it is way too leisurely (i.e., really, really slow) of a pace for most people.
v/r, N-A
Next time, I might try my hand at fishless just to see if I can.
I agree...if you want to get the tank going more quickly, fishless is the way to go. Even though I like the fishy cycle, properly done, it is way too leisurely (i.e., really, really slow) of a pace for most people.
v/r, N-A
Bishop your cycling post should a sticky. I've refered to that post several times for my fishless cycle 
Letsgometsreyes said:
More experienced people can tell you better than me, but I would not waste money on the bio-spera. Yes it works, but it's expensive and you would have to buy more than just 1 bottle for the size tank you have. The bacteria is going to happen naturally without spending $30 on bio-spera.
I've read on this forum that people have cycled there tank in less than a week or even a day using bio-spera
