New Tank Cycled - Levels a bit off

[Skyhawk50E]

I just cycled a new tank using dry rock and live sand.

Been up for 4 weeks. Finished cycling probably 4 or 5 days ago.

Did a 50% water change yesterday to get my nitrates to a manageable level (now at 10).

Today tested all parameters before adding CUC.


Temp: 79.3
Salinity: 1.025
pH: 8.03
Phosphate: 0.03
Calcium: 430
Alk: 7.3
Magnesium: 1170


Is that low alkalinity and magnesium normal for a new cycled tank? I would of figured after a 50% water change with reef crystals, they would be a little higher.

Do I just need to give it time?

 

[saltyfilmfolks]

Minor test error is common.
Really really really common.

The only thing you really need to know right now is ammoina and salinity. IMO.

 

[SeahorseKeeper]

Minor test error is common.
Really really really common.

The only thing you really need to know right now is ammoina and salinity. IMO.

I would also add that nitrite and nitrate are also important.

 

[saltyfilmfolks]

I would also add that nitrite and nitrate are also important.

Not an argument or insult. Just adding to the discussion.

How would that effect fish and Inverts?

 

[SeahorseKeeper]

Not an argument or insult. Just adding to the discussion.

How would that effect fish and Inverts?

Nitrite is highly toxic to fish as well as some inverts. Nitrate is not as toxic as nitrite, but it also helps to fuel algae growth.

Personally, I like to monitor all three when cycling a new tank. When cycling, I like to see the ammonia spike up and fall. Then, I expect to see the nitrite rise when the ammonia is converted to nitrite. Finally, I expect to detect nitrates. There have been times when I have cycled a tank and I do not detect nitrite, but I would never add any livestock to a tank that has nitrite. Also, I try to maintain lower nitrate levels so I am not fighting myself with algae blooms.

 

[Skyhawk50E]

Thanks for the input. I monitor(ed) ammonia and nitrite as well during my entire cycle. Both at 0 now, and have been even while ghost feeding. The system is processing it quick.

Just started testing the others (cal, alk, and mag) for my corals, which I wanted to introduce slowly to my new tank.

Just wasn't sure if those low levels were normal just after a cycle.

 

[saltyfilmfolks]

Nitrite is highly toxic to fish as well as some inverts. Nitrate is not as toxic as nitrite, but it also helps to fuel algae growth.

Personally, I like to monitor all three when cycling a new tank. When cycling, I like to see the ammonia spike up and fall. Then, I expect to see the nitrite rise when the ammonia is converted to nitrite. Finally, I expect to detect nitrates. There have been times when I have cycled a tank and I do not detect nitrite, but I would never add any livestock to a tank that has nitrite. Also, I try to maintain lower nitrate levels so I am not fighting myself with algae blooms.

At what concentration is nitrite and nitrate toxic to marine fish?

 

[SeahorseKeeper]

At what concentration is nitrite and nitrate toxic to marine fish?

Welp, I have just been educated. Thank you! It isn’t toxic in marine environments. Guess I have been using my freshwater knowledge a little too much and it might also explain why I have never seen a nitrite spike when I cycled any tanks. I would still monitor those to see if the tank is cycled and would try to maintain nitrate on the lower side. The reason to keep nitrate lower would be for algae control, not the health of the fish.

 

[saltyfilmfolks]

Welp, I have just been educated. Thank you! It isn’t toxic in marine environments. Guess I have been using my freshwater knowledge a little too much and it might also explain why I have never seen a nitrite spike when I cycled any tanks. I would still monitor those to see if the tank is cycled and would try to maintain nitrate on the lower side. The reason to keep nitrate lower would be for algae control, not the health of the fish.

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