Alk Raising with no inputs

[blazerino]

I recently switch from tropic marin pro-reef to classic due to lack of availability. The classic has a higher alk so my alk was slowly creeping up from 7.8 to 8.6 due to AWC with the higher alk salt.

I stopped AWC because I was trying to raise nutrients to beat off dinos, however my alk continued to rise to 9.4 with no water changes and no dosing. Coral load is pretty light, just a few small frags of sps and lps.

Any idea what could be causing my alk to raise without inputs? My PH varies from 7.7-8.3 over 24 hours.

 

[Randy Holmes-Farley Verified Community Expert]

I recently switch from tropic marin pro-reef to classic due to lack of availability. The classic has a higher alk so my alk was slowly creeping up from 7.8 to 8.6 due to AWC with the higher alk salt.

I stopped AWC because I was trying to raise nutrients to beat off dinos, however my alk continued to rise to 9.4 with no water changes and no dosing. Coral load is pretty light, just a few small frags of sps and lps.

Any idea what could be causing my alk to raise without inputs? My PH varies from 7.7-8.3 over 24 hours.

Top off is what?

Might nitrate be declining? (that adds alkalinity)

 

[blazerino]

Top off is ATO RODI.

I did dose neonitro a few days ago to raise nitrates. I was planning to retest tonight.

 

[Randy Holmes-Farley Verified Community Expert]

Top off is ATO RODI.

I did dose neonitro a few days ago to raise nitrates. I was planning to retest tonight.

That would raise alkalinity, and it may also be test error.

 

[blazerino]

That would raise alkalinity, and it may also be test error.

I tested my nitrate and PO4 last night and my nitrate had held steady at 5 PPM from a few days ago, however my phosphate has gone up from .03 to .17.

The bottle of neonitro says something about my system being carbon limited if the numbers do not drop. Is this correct? If so, should I be dosing carbon with vodka or something similar?

 

[Randy Holmes-Farley Verified Community Expert]

I tested my nitrate and PO4 last night and my nitrate had held steady at 5 PPM from a few days ago, however my phosphate has gone up from .03 to .17.

The bottle of neonitro says something about my system being carbon limited if the numbers do not drop. Is this correct? If so, should I be dosing carbon with vodka or something similar?

Are you dosing during that steady period? If you are dosing nitrate and it is staying steady, it is being consumed and there's no issue. That will raise alkalinity.

Phosphate is not impacting alkalinity noticeably.

 

[blazerino]

Are you dosing during that steady period? If you are dosing nitrate and it is staying steady, it is being consumed and there's no issue. That will raise alkalinity.

Phosphate is not impacting alkalinity noticeably.

I only dosed nitrates once to bring up to 5 PPM. Levels haven't moved since then. Only inputs were food since then.

 

[Randy Holmes-Farley Verified Community Expert]

I only dosed nitrates once to bring up to 5 PPM. Levels haven't moved since then. Only inputs were food since then.

OK.

I'd just keep watching it. I think it is not that likely to keep rising.