Cycling Question #2,368,421

[MrLang]

What is the shortest period a tank can cycle?

 

-Set up 20g tank with live sand and a dry rock a little less than 2 weeks ago

 

-Added 8 lbs live rock from LFS about 10 days ago - half Pacific and half aquacultured

 

-Added shrimp -> watched ammonia go up to 1 ppm by day 4 (it was actually 1ppm on day 2 and didn't get any higher by day 4) and pulled it out, so that was about 6 days ago

 

-Been testing daily - today and yesterday my ammonia is 0, nitrites .25ppm, nitrates 20

 

-In the past few days my fresh white Marco rock has been getting brown and bleached parts of the LR have been browning up as well as greening up (been running my lights). There is some GHA growing and green spreading every day.

 

Is that last .25ppm nitrite going to take 2 more weeks to get to 0 or am I just about done? I plan to add only CuC and maybe something extremely hardy until mid March since I'm going away for a week. What would YOU do at this point? My live rock was well cycled and wasn't out of the water for more than 30 minutes. Is it possible when you buy nice cycled rock that it's already got a healthy colony of bacteria going and doesn't need as much ramp up time?

 

Thanks!

 

 

[cju84]

Don't add a CUC until your nitrites are zero and nitrates are <20ppm.

 

How long can a cycle tank? It could be as little as one day if you're getting live sand/rock from an established tank. There doesn't necessarily have to be a cycle at all. Typically will take a month if starting from scratch.

[CCXGT]

I cycled a 10G in around 23 days using live sand, 6.5lb dry rock, 1.2lb live rock.

 

I'd also recommend Ammonia dosing over decaying organics.

 

Makes it much easier if you know what's going into your tank.

[Partially Submerged]

I'd recommend no ammonia at all if you use live rock/live sand (though I find the latter questionable). Live rock - unless treated poorly during transit - is capable of processing ammonia/nitrite from day one. Some would say that's the point of getting live rock because that's the point of getting live rock.

 

Now, if you are planning on heavily stocking the tank, then yes, you could increase the population of bacteria by adding an ammonia source, but it makes much more sense to introduce your livestock very slowly and gradually. I'd start with a few snails.

 

0.25 ppm of ammonia should not take more than a few hours to go down to zero. There is no such thing as the last 0.25. Chances are you have an API test kit, which tend to read 0.25 even if you have 0. An easy way to test this is to get a bottle of diluted household ammonia from the hardware store (make sure it has no additives) and add a few drops until your test reads 0.5 or so. Then measure again a few hours later. If your levels are down to 0 or "0.25," your tank is ready for livestock.

[Azedenkae]

I would recommend ghostfeeding and monitoring the parameters changes. That is how I determine thatmy tanks are cycled. Basically if you add food and the filtration is able to deal with it, you are set.

[MrLang]

Thanks! All of this makes sense. Since I plan to add very slowly anyway I'll give it a few more days, do a water change, and add 2 or 3 snails. The science of it all makes sense to me but I read a bunch of cycling threads many of them boasted about 3 week cycles being quick so I was skeptical. And I am using the API kit, another reason to be skeptical.

[Azedenkae]

Thanks! All of this makes sense. Since I plan to add very slowly anyway I'll give it a few more days, do a water change, and add 2 or 3 snails. The science of it all makes sense to me but I read a bunch of cycling threads many of them boasted about 3 week cycles being quick so I was skeptical. And I am using the API kit, another reason to be skeptical.

I use API as well, no issues with them for me.

 

The initial cycle can be anywhere between non-existent to taking months. So three weeks is nothing to be skeptical about. Do it right and the initial cycle should never be long. I just finished cycling mine, took 10 days.

[MrLang]

#2,368,422

 

Can someone give me a sanity check on this? I have done my homework but there's something reassuring about a 'live' response.

 

Levels:

 

pH: 8.2

kH: 8

 

Calcium: 360

Phosphate: .25

 

Ammonia: 0

Nitrite: 0

Nitrate: 20

 

Salinity: 1.024

Temp: 78-79f

 

 

I am thinking I just need to do a big water change to lower the phosphate and nitrate and I'm good to add CuC and a few hearty corals?

 

How do I raise my calcium / which corals are particularly sensitive to low calcium?

 

Am I missing anything else here?

[Azedenkae]

You can dose calc separately to raise calc.

 

That phosphate level is fine for corals.

 

More importantly, have you tested your filtration capacity? It is important to ensure that your aquarium has cycled properly. 0 ammonia and nitrite is an indicator that it may have finished, but is not definitive.

[MrLang]

Thanks - and good point.