Cycling New Tank Question

[werkkrew]

I have finally finished setting up my new tank 100%.

The setup is 30G display / 20G DIY Sump, 45# Live Rock, shallow sand in display, deep in fuge.

It has been circulating water for about 4 days now and I decided to check the ammonia levels to get an idea if the tank was cycling or not. I was expecting high levels ammonia but the levels came back as trace (< 0.5g/l).

My water quality is 82deg F, 1.025 SG, 8.2 PH. I didnt do all the other tests since there is no livestock.

Obviously the tank has not cycled yet but I am wondering why after 4 days my ammonia levels are so low. Will they climb slowly, rapidly?

What should I expect/watch out for over the next few weeks?

I am expecting the rock and sand to take about 4 weeks to totally cycle in this setup.

 

[reefworm]

was the live rock cured? if so, not much dead or dying matter to contribute ammonia to the system. you could throw a piece of shrimp in the tank and let it do the job for you.

 

[bertoni]

I wouldn't add dead shrimp to a tank with live rock. I don't see any benefit. If the live rock was clean, low or zero ammonia is fairly common. I'd still wait a couple of weeks, and do some water changes.

 

[snorvich]

And check nitrite. It also should be zero at some point.

 

[werkkrew]

I bought the live rock from a LFS it was sitting in large vats of salt water so Im guessing it was patially cured but the employees there said it was uncured when I asked.

The rock clearly has lots of organic matter on it, so I can only assume some die back needs to take place.

I used about 10lbs of cultured live sand mixed with the rest of my argonite in my mix so there is a small chance that bacteria is already growing but I doubt it.

I plan to wait a few weeks nonetheless but as of right now my water chemistry seems livestock ready, I am sure I will see an ammonia spike in the next week or so.

 

[canman]

I suggest waiting for awhile let the tank get a real good cycle period, don't be in a hurry to get the tank filled. I know it gets boring looking at rock and water, but patience is the key to this hobby I learned the hard way.

 

[bertoni]

If you're worred, you can test the presence of a biological filter by adding small amounts of fish food every day for 2-3 days.

 

[werkkrew]

I am not in a hurry at all, when I said that I think the tank is livestock ready I wasn't trying to say that I was actually going to add anything.

The idea of adding fish food every day to stimulate an ammonia spike sounds like a decent idea but I think I will test ammonia again every 2 days or so until the end of the week to see if I get a spike from the rock alone.

Thanks for the advice by the way.

Is there anything else I should be doing/watching out for over the next few weeks or do I pretty much leave it alone?

I have read mixed opinions on cycling methods, some say to do 50% water changes weekly, others say to not change the water at all during the entire cycle.

 

[reefworm]

IMO large water changes will just slow down the cycle. Compliments on your patience - you'll do well in the hobby If you saw organic matter on the LR, and it was displayed as you describe then I would agree with Bertoni that the shrimp is unnecessary. Pretty much leave things as they are for now, testing as you plan to, and just watch for the inevitable cycle of algae blooms as things settle in.