Cycling a tank, adding fish and corals


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First off, if there is anything you believe I have left out, tell me and I can add it into this guide.

I also think we should sticky this to the 'new to reefing' area as its most appropriate here

How to cycle your reef tank and when you should start adding fish.

First of all, there are a number of items you will need in order to cycle your tank, know when your tank has finished cycling and whether or not it is safe to add fish and corals.
· Saltwater Test kit – you will need a test kit which tests:
[FONT=&quot]o [/FONT]Nitrates
[FONT=&quot]o [/FONT]Nitrites
[FONT=&quot]o [/FONT]PH
[FONT=&quot]o [/FONT]Ammonia
· Other useful tests are
[FONT=&quot]o [/FONT]Phosphates
[FONT=&quot]o [/FONT]Calcium

There are various methods on how a person may cycle there tank. The most commonly used and easiest method will be the one that I will demonstrate below. For this you will need:

· Live Rock
· Live Sand
· Salt water – at the correct salinity (between 1.024 and 1.026) refractometer is the best for this
· Powerhead (to create flow in the tank)
· Heater (in order to determine correct salinity and create right environment for fish)

First off, create your sand bed for your tank with the live sand you have purchased. When you do this, you need to determine how deep your sand bed will be. The deeper the sand bed, the more Cleaning crew you will need in order to turn over the sand as to not create Nitrate bubbles under the sand bed. Now you can fill your tank, I choose to use a bowl or a slow siphon in order not to stir up too much of the sandbed through this stage.

Now that your tank is full, you can add your live rock in whatever pattern you choose and think is aesthetically pleasing. This live rock will do most of the work in cycling your tank. At any time in this stage, you can add your heater and powerhead, but make sure that the powerhead is not running out of the water as damage will occur.

Most reef tanks will take about a month to cycle through, but the cycle can take anywhere from 2 to 8 weeks depending on how much dead material was on the live rock when you first added it. Make sure you don’t decide your tank is ready without doing the tests and seeing that your nitrates, nitrites and ammonia are 0. If you do, you will have deaths in your tank. And the biggest rule here is: NOTHING GOOD EVER HAPPENS QUICKLY IN A REEF TANK.

While cycling your tank, you can do the following:

· Run your lights
· Skimmer
· And have your refugium running properly (suggested)

Inversely, while cycling your tank you should not:

· Do any water changes
· Add animals to your tank

If you have purchased your test kit before cycling your tank, you will be able to follow the cycling process as it occurs.

Following the cycle

Step 1
The first thing you will see is a spike in ammonia a few days after the tank has begin to cycle. You should test this every 3-4 days and through this, you will see the ammonia continue to rise until eventually, it becomes 0.

Step 2
The next thing you will begin to test will be nitrites and you can follow the instructions in step 1 and eventually you will see the nitrites drop to 0.

Step 3
The last step is to test your nitrates and these will end up being very faint or 0. When you get to this point, your tank has most likely gone through its cycle. It is recommended that you take a few days to wait in order to make sure that the tank has definitely completed its cycle

Adding life to your tank

The first thing you should start to add to your tank is inverts. Inverts are known as your cleaning crew and are very important to having a live, happy tank. You should begin to add these very slowly, only a few at a time in order to keep bio load at a minimum and to let everything establish itself in the tank.

Without fish, your inverts won’t have as much food available to them, so don’t add too many inverts to your tank without having some fish for them to clean up after. After having your inverts for 1-2 weeks in the tank, you can start adding fish. The suggestion is that you don’t add any more than 50% of your tanks capacity in fish, but it is suggested to add less than this in order to let all fish acclimate to the tank and in order to keep the bio load steady in the tank. When stocking your tank, you should not have anymore than 4" (10cm) of small-to-medium fish per 10 gallons, or 2" (5cm) of larger/fast growing fish per 10 gallons.
So with this rule, you can determine your maximum amount of fish you can have in your tank depending on the size of the fish. The only problem with this is some tanks can stock more or less than this number depending on the filtration systems available. So make sure, after you add fish, you continually check your water levels in order to make sure it is safe for your animals.
Adding corals

Before you add corals, you need to make sure that your lights are sufficient for the tanks and there is enough flow in the tank.
For flow, it is suggested that your tanks water volume gets moved around 10 times in 1 hour. Depending on the size of the tank, you may need multiple powerheads and you must use your own common sense to work whether there is enough flow.

All animals in your tank, you cannot add animals without it and should never attempt it. For corals though, there is a higher requirement for light and a formula is available for you to work this out.

To have corals, we require at least 4 watts per gallon of water in the tank. This is a minimum and some animals such as clams or anemones may require a higher amount of light in your tank.

If you have a 50 gallon tank, it is suggested that you have 200 watts of lighting, but the type of lighting also makes a difference. A normal light will not be good enough for corals. The best lights for a tank are:

· T5 lighting
· Metal Halides
· LED lights designed for reef aquariums (very expensive)

Without the correct lighting, your corals will die quite quickly.
It is recommended also that you get a timer for your lights. There is no need to run your lights all the time and nor should you. If you run your lights more than 10 hours a day, you are doing your tank harm by promoting the growth of algae in your tank.

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Thanks Joey, hopefully it helps someone, because its most of the starter questions i didnt know before!
Good read josh :). Question though, when first adding the CUC will they survive off the live rock and algae? Or will you need to give them very tiny feedings?
they should be able to survive off the live rock and algae for a small amount of time. But the idea is not to put too much CUC in the tank early, just a small amount before you add the fish in. you generally add fish about 2 weeks after putting your first batch of CUC in the tank.

If it is more comfortable, you can add tiny feedings, but these are quite small as to not create a load on the tank from uneaten food.
haha, good job Jmck. Nice job taking initiative.

Although you might want to alter 1 or 2 things in there:

The nitrate is actually the end product in the bacteria cycle(it will be greater than 0), and the only thing that uses this up is photosynthetic plants(Algae). So as long as your tank is 0 ammonia/nitrite your good :) most ppl do water changes once those are 0 to lower the nitrate(End product)

Bacteria Cycle textbook explanation:
[ame=""]YouTube - Aquarium Care, Biological Filtration, and Cycling[/ame]

Also there are different ways to go about the cycle, but common types are:

- Addition of live rock (Best method imo and was what you chose, good choice!)
- Add a piece of raw shrimp and wait..... (longer method I think, and might not completely fulfill a tanks bacteria population.)
- Add a hardy fish(Damsel or Chromis) and slowly their waste/extra food will start the cycle. (This method is not so much recommended but if so you have to check ammonia and nitrites daily and do water changes to lower them if they start to spike) Fish may not survive this method! :(
- Just keep adding fish food into your tank, this will start to decay and start the cycle.

remember, the more decay there is the more bacteria it produces. If you use a method that does not create much decay your bacteria populations will be small and you will have to be careful adding livestock as this can cause "mini cycles".
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That is very true about the nitrate, but with the addition of just live rock, you will generally end up with very faint and often 0 nitrates. Its the beauty of just using live rock to cycle your tank. This was my ending and did not have to do a water change for a while after adding fish.

And there are many options and all are valid.

Keep in mind you can use the other options that have been presented by Ulta, just please do not use a live damsel, that is just cruel imo

and with the mini cycles, if you add animals slowly, your bacteria levels will continue to rise without causing this, it comes down to patience! so please take it slow.

I might do a revision of this article and add a few more things into it soon, thanks for the suggestions Ulta :)
Thanks..You answered some of my questions.I'm new and doing research before starting.a protein skimmer is it really necessary?I've read live rock and water changes is just as good.and wat would be a good skimmer afordable?
It depends on what size tank you have. For smaller tanks, a skimmer isn't necessary as water changes will take care of it. But for larger tanks, they are invaluable because larger water changes are a hassle to do. If you don't get a skimmer, you will have to do bigger water changes more often.

Octopus is a good brand. They make affordable skimmers.
Thanks.a lot of help..well I've decided to do a small saltwater setup.I will be cycling a 20 gallon with live sand and live rock.and fish flakes...after my cycling is done..wat good cleaner or janitor fish is recommended?...I'm thinking of a simple anemone with clownfish..any advice.
I don't think you should add an anemone -- they are not simple. They are harder to keep than most corals and require pristine water conditions and excellent light. Clownfish are a good choice. If you're looking for the interaction of the clownfish and anemone, there are lots of easy to keep corals that clowns take to that would be a better choice than an anemone.

There really aren't too many cleaner or janitor fish in saltwater. We rely mostly on snails, crabs, starfish and shrimp to be janitors.
Mario, glad this article helped :) biff is right, stay clear of anemones till the tank is established, your water is pristine, your lights are strong enough and your tank is old enough.

Torch corals can act very similar as anemones to clowns and clowns will play and host them, mine started off on a torch coral but now have an anemone as im confident enough.