Nitrogen Cycle Issues

mirosh · 10-23-2004, 12:04 PM

Hello All,

I added 25lbs of LR to my 25 gal tank about a week ago and have been taking readings of Ammonia/Nitrite/Nitrate every day. I don't seem to be getting the results I expected I would get as the tank went through the nitrogen cycle. The rock I bought was Fiji, semi-cured live rock from my LFS. They said I would still need to let it fully cure and go through the Ammonia and Nitrite spikes before adding life, but I didn't really see spikes, except for in the first few days.

Here is what I got so far (on 10/14 I added the rock and a cocktail shrimp, at about day 3, it smelled a little bit, but the smell only lasted a day or 2):

No code has to be inserted here.

As you can see from the above table, the ammonia and nitrite went through VERY brief spikes, and now the nitrate is pretty much levelled at ~20 ppm. Are there any problems with how fast this nitrogen cycle went (about a week). My pH is steady at 8.2 and the SG is about 1.023-1.024 (steady).

What do you thinK????

Thanks for all of your help!

-Mike

fletch · 10-23-2004, 01:47 PM

Try putting a Raw shrimp in the tank and let it stay there for a while, The decaying shrimp will raise your Ammonia level and get your cycle off to a good start.

................ John

mirosh · 10-23-2004, 01:59 PM

I put the cocktail shrimp in on the same day I put the LR in and it decayed within 4 or 5 days. I didn't want to put more than 1 shrimp in because it is only a 35 gallon tank! It was totally gone by about 10/20/2004!

Any other reasons why the cycle might have gone so quickly and/or why it didn't cycle properly!?!?!

fletch · 10-23-2004, 02:12 PM

What do you have for substrate in your tank

fletch · 10-23-2004, 02:38 PM

Myself I would add a couple more shrimp

...... John

JohnO · 10-23-2004, 03:20 PM

Hi Mirosh :-)

So the tank had water ( with sand ) about a week before the LR went in? If that is the case then I think the tank has cycled. Remember that the level of the Ammonia spike is directly related to the amount of decay ( from the LR and shrimp ) and the level of Nitrite is related to the level of Ammonia.

So if you have seen Ammonia, Nitrite and Nitrate there must have been a cycle no matter how large.

IMO you have 2 options. Either add one small fish or put another ( large ) shrimp in the tank to keep the cycle going.

If you choose the fish option, just make it a small one and wait for a couple of weeks before adding any more. If you opt for the shrimp then let it decay and if after 2 weeks you still have no Ammonia or Nitrite levels then add a fish.

Either way would be OK IMHO and if it was me I would add a small fish :-)

JOhn

fletch · 10-23-2004, 03:43 PM

I don't know JohnO But you would know better than I !
But that is an offal fast cycle IMO 9 days

..... John

JohnO · 10-23-2004, 04:01 PM

John,

The thing is if you put a tank of saltwater in the middle of the Sahara dessert, no rock, no sand, nothing but water it will start to cycle. So in fact the tank has been cycling for 16+ days, not just 9 :-)

The bacteria that cause the Nitrogen cycle are everywhere ( in the form of spores ), you really dont have to introduce them by means of LR or anything else. They are the same types of bacteria ( different species ) that cause meat or vegetation to rot :-) Yuck :-)

John

fletch · 10-23-2004, 04:08 PM

[quote author=JohnO link=board=Newbie;num=1098569059;start=0#7 date=10/23/04 at 19:01:14]
John,

The thing is if you put a tank of saltwater in the middle of the Sahara dessert, no rock, no sand, nothing but water it will start to cycle. So in fact the tank has been cycling for 16+ days, not just 9 :-)

John[/quote]

When did he set the tank up?

saltyfish922 · 10-23-2004, 04:09 PM

Are you saying that you can cycle a tank with nothing in it?