Saltwater cycle

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It's me
Jan 26, 2004
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S.W. cycle


Hello, there are lots of threads across the net about people trying to set up salt water tanks. Any house needs to be built on a good foundation so, I thought that I'd write a little about the cycle. There are several methods that are used some work better than others but, you can have success with several.
1. The fishy cycle one in which the hobbyist introduce fish and a bacterial culture to a tank. This is unfortunately the method that is used the most and well probably works the least well. I'm only covering it because so many people end up in this situation by being given bad advice and can't get out of it. A lot of fish stores won't take critters back after they sell them so, the individual is stuck.
A. Problems with doing this are actually pretty major such as the fact that your tank will only be cycled for the number and size of fish that you introduced to your tank. These fish tend to be damsels and most of them aren't at all reef safe and are a real pita to catch! You also run the risk of introducing a pathogen when you use fish and you don't want to ever have to treat your main tank. Not to mention the fact that it's bad for the fish! There couldn't be anything worse than loosing your first pet fish in the cycle ," well except loosing other fish when you introduce them and never being really sure why."
Also, I've found that people doing a fish based cycle are far more likely to use crushed coral as a substrate. I understand in a fish only set up that it may not be as much of an issue as in a reef or a mixed tank but, it causes long term pollution problems. The crushed coral picks up a large of wasted food, feces and more. I use a deep sand bed myself but there are many other styles a regular sand bed or bare bottom use which ever style you like. I'll stop this now it's a whole other thread.
2.My favorite .
Cured live rock. In my humble opinion this is the best way to go and probably the most expensive. Place the proper amount of live rock,"1 to 2 lbs per gallon," in the tank fill with water and go for it! Nah, just kidding it's not quite that simple a lot of live rock has lost most of the critters and bacteria in the curing process. So, you have to find a way to encourage the bacteria to grow and in a reef increase the diversity of your small life. What I do is this I fill the tank with 90% cured live rock and about 10% uncured live rock. Not only does that introduce an ammonia source but, it also introduces a myriad of little critters that didn't make it through the process. You should keep an eye on your ammonia levels but, I've never really had any problems at most I've had to do a couple extra water changes. This is probably the quickest way to go and IMO the best.
You can also use all cured live rock and either a. slowly introduce your fish so as to give the bacterial populations time to reach sufficient populations to manage fish waste or you can add ammonia to the tank to stress it and give your bacteria a food source. I know what you're thinking which way's best Max? What I do is both add enough ammonia to bring the tank up to .05 or so and check your water in a couple of hours do you still have ammonia readings? . If not you're ready to add you first fish or couple of small fish check your water and see if you ever get ammonia or nitrite readings? If so water changes if not keep on going until you're done stocking.
Please keep in mind that some live rock is really pretty much just base rock that has sat in water for a while. It has little or no bacterial population so always buy from a reputable source.
Uncured live rock
This is a little cheaper than buying cured live rock but, you'll have to do more work. U.C.L.R is live rock that's been collected fairly recently and hasn't been through treatment to remove the critters on it. A lot of critters like sponges etc. die on contact with air. Their rotting bodies provide the needed ammonia to cycle your tank. Make sure you remove any large dead critters and as much sponge as possible . Keep your readings under toxic levels by doing water changes and you'll be amazed at the bio-diversity in your tank. This might require several changes a day though if you don't want to nuke the critters that live on the rock. In short it requires more time but, it can even be more rewarding than the cured live rock method.
Hybrid method
I normally refer to this as the 50/50 method you fill your tank with 1/2 ,"more or less is ok to," uncured live rock and 1/2 base rock or dry coral rubble. Keep your parameters in check and the bacteria and most of the critters will move to the base rock. You can save your self a couple 100 on larger tanks and have the same affect as all live rock. You can also do this with cured rock but, you have to be a bit more patient.
3. mostly artificial
This requires the most time but, it will give you nearly total control over what goes into your tank.
Fill tank with desired amount of base rock and a small chunk of cured live rock or other innoculant and dose with ammonia .1 is fine with this there isn't anything in the tank that you can kill. On that note I'd keep the temp at 85f or maybe a little more to speed up the process a bit.. Test water parameters until your cycle is done . Then add fish and other critters slowly until you reach the desired affect. I would also encourage you to purchase cultures or small critters like vermatid worms ,pods etc and add them after the cycle.
4. To sum up.
The cycle is a bio chemical process that's carried out by bacteria. It converts organic waste into atmospheric nitrogen keeping your tank habitable for your fish and critters. There are a few ways to rush mother nature but, you probably shouldn't use them except in a very few cases.

I hope that this helps someone out and if anyone would like to add how to do this for fish only or fresh water it would be greatly appreciated as would comments and criticisms.
thanks and enjoy.
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