The Nitrogen Cycle

snakeblitz33

Well-Known Member
Introduction

It wasn't until Dr. Jaubert discovered that after he had killed off all of the new fish and coral additions in his tank and got fed up with the whole system that he let the tank sit in the corner of the room stewing. Not giving up, he decided to start the tank again, but this time without taking it completely down and setting it up. Using the same water, he discovered that if you let a marine tank sit idle for a while, the system would somehow balance itself and make living conditions suitable for marine life. Let us discuss what happened and how to do it.

The Process (es)

1. The most often prescribed method of cycling a tank is simply putting a small piece of shrimp in the aquarium, along with new salt water and new live rock and let it sit white the water circulates. This method has been tried many, many times and has proven that it is the safest and easiest way to cycle a tank.

2. The ammonia method is a bit different and the process is much more convoluted. A .1 mol solution of ammonia is mixed up, of which one drop per ten gallons of tank water is used. Once, every other day until the ammonia and nitrite levels drop to zero. This process, even though a proven method, can add too much ammonia to the water and create algae problems in the future.

3. The fish method - Some life fish stores recommend that you add one small fish to a tank that you just started. more than likely, it will be a cheap fish, such as a damels. What the fish store doesn't tell you is that the ammonia in the water will eat up the fishes gills and cause it great pain and respiratory distress. While some fish make it through the process, if it makes it through a live, you will have to remove the fish from the tank if you don't prefer damels in your tank. They are mean and very aggressive fish. If you chose to go with a different, more expensive fish, you still risk the chances of it dying or suffering pain.

The Chemistry

Ammonia -> Nitrite -> Nitrate
NH^4 -> NO2 -> NO3

Ammonia is very harmful to almost every living organism in a marine tank except for certain bacterias. Ammonia is transformed into a less toxic but less stable chemical called nitrite. Finally, the end product is called Nitrate, which is relatively harmless to fish, but can cause problems with algae.


The Biology

Ammonia is released from any dead or decaying matter in the tank. When you start a new tank with uncycled live rock, the decay causes ammonia to build up in the water, and there is not enough bacteria to deal with the excessive amounts of it. This is where a group of bacteria called Nitrobacter come to process the ammonia into a less harmful substance called nitrite. Nitrosomonas bacteria then convert nitrites into nitrate. These different bacteria have different biochemical pathways that need the basic building blocks to carry on their life processes.

The Physical changes

Your tank will probably start off looking very clean, with no algae except what might be on the rocks. It will not stay this pristine. Algae uses ammonia and nitrites and phosphates to grow, and as these chemicals are introduced in the aquarium, different forms of bacteria will grow in the tank and different types of algaes. The first to appear is diatoms. Diatoms look brown and they seem to dust everything in a fine to thick laywer of brown. The next succession is of green and brown slime algae that developes on the glass, rocks, and other hard surfaces of the aquarium. These types of algaes can be simply wiped off with a magnetic scraper. Towards the end of the cycle, you will see higher order algaes starting to develop. You could quite possibly see the starting stages of hair algae, bryopisi or even beneficial algaes called coralline algae.

Keep in mind, though, that in order for algae to form, it needs a light source. Most aquarists try to leave the lights off during the first initial cycle to keep the amount of algae down.

Testing is as easy as 1, 2, 3, .

You will first test for ammonia. ammonia will reach a peak at about 1.0ppm. and then nitrite will show up. once ammonia goes down , start testing for nitrite. once nitrite reaches zero and ammonia is zero and either none or some nitrate appears, your aquarium has undergone it's initial cycle.

Keep in mind that the cycle never ends. ammonia will always be produced from decaying matter, fish will always produce fish waste and algae will grow and die. Food will be introduced, browken down and have to undergo the process too.

So, pick a method that works for you and try to test every day or every other day. a cycle can take anywhere from one week to thirty days or even longer, depending on the amount of decayed matter on the live rock that you purchased.
 

snakeblitz33

Well-Known Member
My computer was messing up when I wrote the article, so I will have to go back and edit it when my computer starts acting right again.

For the most part, the information written is accurate enough for the layman to understand what the Nitrogen Cycle is and why it is important to understand it.
 

geridoc

Well-Known Member
Pedantic correction: The ammonia method does not add too much ammonia, nut may add too much nitrogen to the tank, which cab be good food for algae. Other than that minor quibble, nicely done, as usual.
 

snakeblitz33

Well-Known Member
I re-read what I said and I think I am going to stick to it. It's a minor thing, but the end product of the ammonia is nitrate. However, I also know that adding macroalgae to a tank with ammonia will also decrease the levels - and I have read studies where algae will remove ammonia from a system. However, like you said, it's a very minor correction and nothing to quibble about. ;)
 

flower

Well-Known Member
I re-read what I said and I think I am going to stick to it. It's a minor thing, but the end product of the ammonia is nitrate. However, I also know that adding macroalgae to a tank with ammonia will also decrease the levels - and I have read studies where algae will remove ammonia from a system. However, like you said, it's a very minor correction and nothing to quibble about. ;)
Dude...LOL..You have to fix even such tiny issues, a good book is hard to find, and we expect your book to be as error free as possible. I hope you can publish some day.
 

beaslbob

Well-Known Member
good article.

but you forgot the "beaslbob build" aspects.

For that condition there is a highly technical term: it's called:



Normal


(LOL)

In that dangerous way of keeping tanks you start the tank full of macro algaes (in a refugium) then let it set a week.

The macros will consume the ammonia directly so there is little to no ammonia and nitrate spikes. But there can be a much safer initial nitrate spike.

Then after the aerobic bacteria build up the nitrates (if sipked) drop down to unmeasureable levels.


So I let the tank run for a week with macros then add 1 male molly. And don't add food the next week and finally add more fish and start feeding very very lightly like 1 flake per day. So you use a $2.00 fish from any fish store to test and extablish the tank.

Then add the more expensive marine only fish later.

the entire don't cycle with live fish simply doesn't apply. the fish never are exposed to any ammoni/nitrIte spikes.


as usual the "beaslbob build" is worth at most.

.02
 
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