levels dropping

[bosslady]

My tank has been cycling for about 2 weeks. The ammonia is .50 nitrite .50, nitrate 20. ph has been at 8.2 steady. Should I be looking for a second spike(I did have one already) in readings or is my cycle comming to an end?

Is it right that I should do a water change before I put in a cleaning crew.


Jeanett

 

[triggers]

Did your ammonia spike off the chart? Cycling usually takes (IMO) 6-8 weeks after you add live rock.

 

[cj10488]

Yes I would def. do a 20% water change once nitrite and ammonia are at 0 me personally I would make sure they stay at zero over a weeks time period to make sure.. Nitrates must be lower than 20 in order to keep most species in a cleanup crew.. As for if your cycle is coming to an end 2 weeks seems quite short... When cycling you should see your Amm. spike and then start to fall.. When Amm. starts to fall you will see your Nitrites Spike.. The nitrite spike should rid your system of amm but you will have the just as toxic Nitrite in your system.. Once your Nitrite starts to fall you will see your nitrates rise.. Since you plan on a clean up crew depending on Species I would wait until the Nitrate is down below 20ppm as well.. When you feel comfortable that your Ammonia=0, Nitrite=0, and Nitrate is less than 20ppm... I believe I am correct but I am still new to SW myself. If I am incorrect someone please correct me..

Approx 6 weeks is the cycle time not including time to drop the nitrates as well for invertebrate

James

 

[Koijoy]

The time and peak of cycle will all depend on several factors. Loading of the system, amount of surface area provided, and the amount of bacteria present in the system.

If a person starts a tank from scratch with no living bacteria( fresh bio balls) in the system the and uses only 1 shrimp or fish to start the cycle it could take over 12 weeks.

If a person starts a tank with live rock and sand as a bacteria seeding the time will be shorter depending on the amount of die off on the rock.
large die off will yeld a higher ammonia spike. little die off will yeld a lower level. The biggest concern would be if you didn't see the nitrite levels go up and then back down to 0 nitrite is the second stage and needs to happen for a complete cycle.

Just because the ammonia or nitrites didn't go off the charts doesn't mean the tank didn't cycle. Bacteria are dependent on food to live (ammonia/nitrites) is food. You will only have a given amount of bacteria on any given surface area for the amount of food produced. The numbers will balance out in the end.

You are doing nothing for a tank if you let the ammonia go off the charts because once the cycle is over the large numbers of bacteria that you produced will decline due to the lack of food.

As you slowly start adding more critters to the system the bacteria will quickly rebound to meet the new demand as long as the surface area and oxygen is available.

Koijoy