Nitrates dropped to 0?

mr.lordacan · Aug 17, 2023

Hi everyone,

Looking for some insight as to why my nitrates have dropped to ~0ppm (API and Salifert, so not a true 0ppm).

My tank was started in May 2022, setup:
- 40B tank, AIO Setup
- Filter socks, protein skimmer (60G rated), carbon, phosgaurd
- 2x clownfish, 1x pink spotted goby, 1x harp tail blenny, 1x chalk bass, 1x cleaner shrimp, assorted CUC
- 11 LPS, 6 softies, 2x BTA, 1x RFA

Parameters:
- Alk: 9-9.5
- pH: ~8-8.2
- Ca: 440
- Nitrates: ~0
- PO4: 0.08ppm (Hanna ULR)
- Mg: 1240
- Salinity: 1.025

Known tank issues:
- GHA outbreak due to leaching phosphates

Response:
- Manual GHA Removal and filter sock replacement 2x/week.
- Phosguard changeouts every 4 days dating back to January 2023.
- weekly 5g water changes

Recent changes in routine:
- All for Reef dosing began ~ early June 2023. Currently at 12mL/day.
- USA orbit Marine LED changes to (2) AI Prime 16HD in ~ late July 2023.

Historically my tank has ALWAYS had a solid 15-20ppm of Nitrates for over a year now. I don’t believe this is a true 0ppm nitrates because I haven’t seen any Dino outbreak and GHA is still an issue (although they would likely be using the PO4 leaching from my dry rock).

But why are my nitrates all of a sudden hitting 0 on my test kits when I previously always had 15-20ppm? I’ve started to bump up the quantity I’m feeding just to try and put nitrates in the water.

Feeding routine:
1x day brine shrimp (Hikari)
1x day mysis shrimp (Hikari)
3-4mL ab+ aminos daily
reef roids 1x/week
Rotifeast 1x/week

For now I plan to stop the weekly 5g water changes until I see an increase in nitrates..

KrisReef · Aug 18, 2023

Sometimes, as tanks age, they eat nitrates. Some people dose them as a result.

Dan_P · Aug 18, 2023

mr.lordacan said:
Hi everyone,

Looking for some insight as to why my nitrates have dropped to ~0ppm (API and Salifert, so not a true 0ppm).

My tank was started in May 2022, setup:
- 40B tank, AIO Setup
- Filter socks, protein skimmer (60G rated), carbon, phosgaurd
- 2x clownfish, 1x pink spotted goby, 1x harp tail blenny, 1x chalk bass, 1x cleaner shrimp, assorted CUC
- 11 LPS, 6 softies, 2x BTA, 1x RFA

Parameters:
- Alk: 9-9.5
- pH: ~8-8.2
- Ca: 440
- Nitrates: ~0
- PO4: 0.08ppm (Hanna ULR)
- Mg: 1240
- Salinity: 1.025

Known tank issues:
- GHA outbreak due to leaching phosphates

Response:
- Manual GHA Removal and filter sock replacement 2x/week.
- Phosguard changeouts every 4 days dating back to January 2023.
- weekly 5g water changes

Recent changes in routine:
- All for Reef dosing began ~ early June 2023. Currently at 12mL/day.
- USA orbit Marine LED changes to (2) AI Prime 16HD in ~ late July 2023.

Historically my tank has ALWAYS had a solid 15-20ppm of Nitrates for over a year now. I don’t believe this is a true 0ppm nitrates because I haven’t seen any Dino outbreak and GHA is still an issue (although they would likely be using the PO4 leaching from my dry rock).

But why are my nitrates all of a sudden hitting 0 on my test kits when I previously always had 15-20ppm? I’ve started to bump up the quantity I’m feeding just to try and put nitrates in the water.

Feeding routine:
1x day brine shrimp (Hikari)
1x day mysis shrimp (Hikari)
3-4mL ab+ aminos daily
reef roids 1x/week
Rotifeast 1x/week

For now I plan to stop the weekly 5g water changes until I see an increase in nitrates..

Maybe the coral are growing, not necessarily consuming the nitrate but consuming the ammonia that leads to nitrate. Algae growth also uses up nitrate and ammonia.

mr.lordacan · Aug 18, 2023

KrisReef said:
Sometimes, as tanks age, they eat nitrates. Some people dose them as a result.

is increased feeding an alternative to dosing nitrates, or are there other drawbacks to this approach?

The_Paradox · Aug 18, 2023

mr.lordacan said:
is increased feeding an alternative to dosing nitrates, or are there other drawbacks to this approach?

Cost and efficacy. If you’re right at the inflection point feeding may be viable. If the deficit is substantial dosing is the way to go. Wait till algae and everything else is where you want it to be before making any major changes though.

Randy Holmes-Farley · Aug 18, 2023

More food can be a fine plan, but it has effects beyond nitrate, such as yellowing of the water, increased phosphate, and O2 consumption.

NCsalt · Aug 18, 2023

This is so similar to what is going on with my 40b. Nitrates poof. I stopped my 5 gallon weekly water change last week to see if i could get a bump.

mr.lordacan · Aug 18, 2023

Randy Holmes-Farley said:
More food can be a fine plan, but it has effects beyond nitrate, such as yellowing of the water, increased phosphate, and O2 consumption.

That’s good to know. Probably don’t want to add more phosphates to my never ending GHA issues lol. I think I’m going to slightly increase feeding and stop water changes for a week. If nitrate are still undetectable, sounds like I’ll be better off picking up a bottle of nitrates for dosing and keeping my current routine until GHA subsides

mr.lordacan · Aug 22, 2023

Update - skipped my weekly water change (Fridays), and currently my nitrates are up to 0.5ppm following some daily heavy feedings.

Depending on nitrates this Friday, I may potentially skip another water change. If I’m dosing AFR, is there any need to do a water change?