Tank cycle question

[Randy Holmes-Farley Verified Community Expert]

Water change was not possible at that moment (10000 ltr system), that was few years ago with commercial stocking. We used to put encapsulated bacteria (Those were used for waste water recycling, now we have various products of these sort in the market but IMO it has various drawbacks). Was just curious to know the chemistry part of it as you mentioned "ACID" and pH drop.

Conversion of ammonia (NH3) or ammonium (NH4+) into nitrite (NO2-) produces acid (H+) and depletes alkalinity:

NH4+ + 3/2 O2 ---> NO2- + 2H+ + H2O

NO2- + ½ O2 ---> NO3-

 

[becks]

what is consuming the Alk? bearing mind the tank has no life stock. Its not a testing error as I thought that at first and tested three times, I also used Aquaforrest Reef salt and done the water change with Red Sea Coral Pro.

 

[Randy Holmes-Farley Verified Community Expert]

As I showed, conversion of ammonia into nitrate depletes alkalinity.

 

[becks]

Haha I never see that when I posted

 

[Randy Holmes-Farley Verified Community Expert]

No problem.

Happy Reefing.

 

[becks]

It's defiantley the nitrites causing the nitrate test to read high because my nitrates have dropped as my nitrite drop.

I tested .25 - .50 nitrites a change from 1ppm
Nitrates 50ppm a change from 100ppm

I'm going to guess when my nitrites read 0 my nitrates will show around 20ppm.

 

[Doob]

Conversion of ammonia (NH3) or ammonium (NH4+) into nitrite (NO2-) produces acid (H+) and depletes alkalinity:

NH4+ + 3/2 O2 ---> NO2- + 2H+ + H2O

NO2- + ½ O2 ---> NO3-

Is there a calcium aspect to this?

I ask because 2 part solutions are supposed to be dosed equally, but someone with a higher bio load would have a higher ALK demand than calcium, no?

 

[Randy Holmes-Farley Verified Community Expert]

That is only true if nitrate is actually rising.

If nitrate is steady because it is involved in denitrification or taken up by algae/macroalgae/corals, the alkalinity is all given back. So the net with steady nitrate is no alk impact.

During cycling is the big time it matters to most reefers.

 

[Doob]

That is only true if nitrate is actually rising.

If nitrate is steady because it is involved in denitrification or taken up by algae/macroalgae/corals, the alkalinity is all given back. So the net with steady nitrate is no alk impact.

During cycling is the big time it matters to most reefers.

Thanks

 

[rock_lobster]

The tank is fine.. The nitrate will eventually all be consumed by algae... Or you may add chaeto to speed up the process. then ready to add livestock once the nitrate is <5.

 

[becks]

Thanks randy, nitrites dropped to 0 and my nitrates dropped to just below 25ppm, so the nitrites as you said gave a false reading, once again thanks for your time answering my post.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks randy, nitrites dropped to 0 and my nitrates dropped to just below 25ppm, so the nitrites as you said gave a false reading, once again thanks for your time answering my post.

Glad things are working out!

Happy Reefing.