Cycling complete?

[DracoKat]

First, I'd like to mention that I am going to wait a few more weeks before adding fish for good measure.

My 75 gal tanks been cycling for two and a half weeks. New sand, mostly dry rock and a few pieces of LR from my established tank. I added an extra piece of LR from my established tank a few days ago.

I've been testing every other day to see the numbers fluctuate and change.
Nitrite went down first two nights ago with low Nitrate. Ammonia went down to 0 tonight with Nitrate. now it's all 0 across the board.

My dry rocks and sand are still white. no signs of diatoms or other algae.
I do see a cricket-like pod in the tank, possibly came from the recent LR I moved from my established tank.

Does this mean my tank is cycled, or do I need to make it "official" with a diatom bloom? should I start turning the lights on? I don't want to do a WC yet (or should I?)

it seems to have cycled too fast. or is it because I added established LR?

 

[saltyfilmfolks]

You are correct is has started the cycle. Bacteria are processing ammonia.
The cycle is weak however. Live sand live rock. They are cycling.
Diatoms algae ugly phase stuff are not actually related to the nitrogen cycle. The have an independent life cycle of their own The merely appear in the early stages of a new tank as micro flora and fauna establish themselves , devour nutrients and disappear as those nutrients fade.
Diatoms are not a given. I never had diatoms in any tank until recently I started a completely dry rock and sand tank.
Every tank is different. Sounds like you have time. Personally I'd wait on the water change just to give it time to cook. And wait till something ugly grows and use it as an opportunity to siphon and clean it out.

Fwiw. The term mini cycle is wrong. And one of my pet peeves. Stirring up gunk and creating an algae or cyano bloom has nothing to do with the cycle. It's just a huge nutrient spike that results in an ugly like a new tank may get.

 

[domination2580]

Diatoms eat silicates. No silicates, no diatoms

 

[Untamedrose]

Feed it...drop a cube of frozen food in like two-three days in a row. Type doesnt really matter, something like what your going to feed the fish like frozen brine shrimp or a chunk of shrimp. If not a cube about what your expecting to feed the tank with what ever your putting in there in the next say 6 months.

Yes it will decay, but so does fish poop.
If your ammonia stays at 0...nitrites stays at 0 it's safe to start adding stuffs. nitriates may go up ...but thats ok they last leg takes more work, but is less dangerous and easy to fix with water changes.

The cycle ammonia eating bacteria sticks more to the LR then it does to glass or water(OR so they say, and it's an old saying IDK about actual studies on such) but IMO a few peices of established healthy LR can make a big difference in cycling times.(thought to be clear I'm taking LR thats not been out of the water more then a few mins..... in one tank and into another. Not well established LR that got sent to a store, shipped to you etc thats a whole other thing)
I've seen it with the tanks I've set up over the years.

 

[DracoKat]

thanks everyone I think at this point, I understand why people "rush" because they think the cycling is done. I was apprehensive about it since it was so short.

I will feed the tank to get some ammonia build up in there and see how it goes

 

[TheEngineer]

Feed it...drop a cube of frozen food in like two-three days in a row. Type doesnt really matter, something like what your going to feed the fish like frozen brine shrimp or a chunk of shrimp. If not a cube about what your expecting to feed the tank with what ever your putting in there in the next say 6 months.

Yes it will decay, but so does fish poop.
If your ammonia stays at 0...nitrites stays at 0 it's safe to start adding stuffs. nitriates may go up ...but thats ok they last leg takes more work, but is less dangerous and easy to fix with water changes.

The cycle ammonia eating bacteria sticks more to the LR then it does to glass or water(OR so they say, and it's an old saying IDK about actual studies on such) but IMO a few peices of established healthy LR can make a big difference in cycling times.(thought to be clear I'm taking LR thats not been out of the water more then a few mins..... in one tank and into another. Not well established LR that got sent to a store, shipped to you etc thats a whole other thing)
I've seen it with the tanks I've set up over the years.

This. Best way to test, IMO, is to see if the system can handle a bioload. This is called ghost feeding. It's the only method I trust.

 

[DracoKat]

thank you. I dropped a frozen cube of mysis into the tank this morning. great to know there's a "Test" to make sure its good

 

[Randy Holmes-Farley Verified Community Expert]

IMO, a whole cube is more than is necessary.

 

[DracoKat]

I dropped a cube on tuesday. Wednesday I dropped about a half a cube (leftovers from my other fish). Yesterday I dropped about half a cube.

Ammonia and Nitrite is 0 still. Nitrate is between 5.0-10PPM (hard to tell with the colors on API, I will be ordering Red Sea soon)

I threw in some snails from my established reef yesterday to see how they do.

Since Nitrate is low, should I still do a WC or hold off for a while? I am seeing mixed responses on this- mostly if its over 20, then do a WC?

 

[saltyfilmfolks]

i'd let it cook.

 

[Randy Holmes-Farley Verified Community Expert]

I would not bother doing a change at the moment.