How do you know your tank has cycled

[LetoII]

Been a week now testing every other day never had any nitrate/nitrite readings ammonia has always been undetectable. 50 lbs of LR in a RSM 36 gal.

Diatoms look like they have stopped (2 days and my tank had alot of brown... but after that its been dissapearing)

I put 2 frags in after a few days (yellow and gsp) and added 2 fire fish on saturday (one did not make the transition and died after 2 days) the other is going strong active and looks good. 2 Dusters both seem healthy.

Growing some green algae on the walls and my live rock has some green sprouts on it (no idea what it is).

Should I pick up a CUC or has my tank not cycled.

[jbax]

it normally takes about 4 to 8 weeks for your tank to cycle.

[wooden_reefer]

Originally Posted by LetoII

Been a week now testing every other day never had any nitrate/nitrite readings ammonia has always been undetectable.

always 0,0 is either very good or very bad.

Either the medium in your tank has been cycled or a cycle has not started.

The best is to add an ammonium source and test out the tank. Put in 1 ppm ammonia and see how your tank respond.

You may be walking into a calamity.

BTW and FYI, if you don't use QT and cycle for the QT now, you will still be in a calamity if your interest is in fish.

[LetoII]

What is QT?

[sedor]

Quarantine tank. That is a topic on its own, but can be extremely easy and cheap to set up. It sounds to me like your cycle hasn't started. That fish in there will get it going. The best you can do is hope it doesn't die in the process. Only the hardiest of fish can usually make it and a firefish isn't one of em.

[dwd5813]

QT = quarantine. it's a separate system, generally smaller than the display, used to house new fish for a period of observation to avoid adding sick fish to your main tank.

also, you can get some clear unscented ammonia, the kind that doesn't foam up when you shake the bottle. dose sparingly until you get a reading of 1ppm and see if its gone in the next day or so. that will tell you if you have cycled or if it's just starting out.

oops, didn't see that you added fish already. might want to skip the ammonia unless you can move it out. you already lost one too so i'm guessing the cycle didn't really kick off before. be careful, cause you can easily set yourself up for more losses if you keep stocking too early.

[Octoshark]

Originally Posted by LetoII

never had any nitrate/nitrite readings ammonia has always been undetectable

You mean ever since starting the cycle you have never got a reading? That would mean your cycle hasn't even started yet. You need a source of ammonia, then you should get a positive reading for ammonia. Then you should start seeing nitrite, then as nitrite comes down you should see nitrate showing up.

[LetoII]

Good to know. Yeah I know the firefish isn't hardy but I don't care for damsels and hear you can't get them out once they are in. I have spent very little at this point on fish corals ect in fact I've spent more on the epoxy than my polyps. The dusters I couldn't pass up and I'm not too worried about them. The fish were to kick start the "cycle".

[golfish]

did you use cured live rock? or maybe dry rock?

[LetoII]

Cured from a reputable LFS

[dudley moray]

to cycle a tank should only take ten days !maybe 12-14 !
6 to 8 weeks if using uncured live rock and dead sand!

[Chiefsurfer]

chances are, if you didn't have a big drive, you had a VERY SMALL, if ANY, cycle. If it was cured in the tank at the LFS, then it was technically already "cycled" outside of your tank. Did the LFS have fish in the tank with their LR? If not, the bacteria colony is probably VERY small.

You don't need live fish to "kick-start" the cycle. This can be done MUCH cheaper, and nicer to the fish, by using a raw frozen shrimp from the super-market. It is also a LOT more effective at growing large colonies of bacteria than 1(or 2) fish.

I'd test every day, double check your tests against either a friends test-kit, or the LFS kit to make sure your kits are not off. GL on the tank.

[Chiefsurfer]

dudley, how long is it from your house to your LFS? You think that's the same for everyone? What are the chances you think that a piece of rock has a little sponge on it? What do you think the chances are that that LFS bags the rock with sponge on it ENTIRELY under the water?

There are many variables when saying how long a cycle takes. Also, depends on what you call a cycle. Some say once ammonia is gone, the toxic part is over, so the cycle is over(however it is NOT). Some say that once nitrite is done, then the cycle is over. I don't feel it is. I feel the cycle is complete once your ammonia has spiked, and dropped. Then nitrite has spiked and dropped. Then nitrate has spiked and dropped to about 20ppm or less. THEN the cycle is complete. That takes 3-5 weeks I find. If it takes more than that, you have had some unusually large die-off.

If you are at 7 days, have been testing every OTHER day, you may have missed the cycle. It may have hit ammonia one day, nitrite 2 days later, and nitrate 2 days after that. Nitrate should have lingered the longest. IF you didnt get ANY spike, it is entirely reasonable that at 7 days you have not hit any part of the cycle yet.

[wooden_reefer]

Originally Posted by Octoshark

You mean ever since starting the cycle you have never got a reading? That would mean your cycle hasn't even started yet. You need a source of ammonia, then you should get a positive reading for ammonia. Then you should start seeing nitrite, then as nitrite comes down you should see nitrate showing up.

It could also mean the medium such as LR is already cycled as bought.

[wooden_reefer]

Originally Posted by Chiefsurfer

Some say that once nitrite is done, then the cycle is over. I don't feel it is. I feel the cycle is complete once your ammonia has spiked, and dropped. Then nitrite has spiked and dropped. Then nitrate has spiked and dropped to about 20ppm or less. THEN the cycle is complete. That takes 3-5 weeks I find. If it takes more than that, you have had some unusually large die-off.

The term cycle has been around for over 30 years.

By definition, cycling is the graphical up and down concentration of nitrite.

Cycling has nothing to do with the drop of nitrate, by definition.

Again, by definition, cycling is the up and down of nitrite concentration and is about the intensive culture of nitrification bacteria, and only nitrification bacteria.


Definition enables communication among aquarists more precisely. It is not that denitrification is not important in a DT; denitrification is not important in QT for fish. So when I say the medium for QT should be cycled in advance I mean precisely a lot of nitrification bacteria, and not necessarily denitrification bacteria, should be on the medium at the start of the QT.

[tspors]

Leto, by no means am I trying to be insulting, but I find this post disturbing. Your tank is only a week old. You have fish in tank, coral (by the way they also are living animals). You have not even a clue if it cycled. Your last statement "Should I pick up a CUC or has my tank not cycled" What you should do is pick up a book about this hobby and stop torturing animals. Sorry.

[drewp808]

dont take the last post the wrong way, many have started like that, and found out the hard way. only advise is to stop buying from the LFS thats selling you all this stuff becasue the obviously dont care about what they are selling you, they should know better.

[bertoni]

I suspect the live rock was clean, and you're ready to start adding a fish, preferably after quarantine. I wouldn't throw dead shrimp into a tank with live rock, personally. If you're worried about the system or want to add a very large fish, you could try feeding some fish food each day to see whether any ammonia spike results, and to help increase the population of small animals.