High nitrates after cycle and high alkalinity consumption

[Frans1992]

Hello,

I just started my second reef a few weeks ago, and it went trough the cycle. But my nitrates are really high, like 50. And my alkalinity drops very fast. I need to fuel every day with kh buffer from aquaforest and still when I use the max amount it drops almost. This happened exactly the same with my first thank. Is this normal? I started with dry rock and live sand.

 

[Randy Holmes-Farley Verified Community Expert]

The nitrate is likely a false reading from the interfering nitrite. I would not assume you have excessive nitrate.

How much alk are you dosing (in dKH per day)?

 

[Frans1992]

The nitrate is likely a false reading from the interfering nitrite. I would not assume you have excessive nitrate.

How much alk are you dosing (in dKH per day)?

I use KH buffer from aquaforest:

https://aquaforest.eu/en/product/kh-buffer/

Dosage: dissolve 80 g of KH Buffer in 1000 ml RODI water. Dosage should be determined by your water test results and coral’s daily consumption. Before applying KH Buffer solution into the water, it is recommended to run a water test to check current water parameters. 100 ml of KH Buffer solution raises KH level in 100 l (27 US gal) of water by 2,6 dKH. The product is also suitable for casual use for one-time KH level raising. 10 g of KH Buffer in 100 l of water raises the KH level by about 3,3 dKH (Alk. 1,18 meg/l). We do not recommend raising KH level by more than 0,5 dKH per day.

This is my calculation to determine the ammount I need to add.

Aquarium Red Sea Reefer 350 (350 liter)

350ml to raise my 350liter reef tank with 2.6dKH

350/2.6x0.5=67.31ml for 0.5 dKH raise.

Aquaforest state that I may only raise with 0.5dKH a day. Maybe I may at more because my aquarium uses more than 67ml to raise it with 0.5dKH a day.

Futher you state that nitrate is interfering with nitrite. But my nitrite reads zero at this moment.

 

[Randy Holmes-Farley Verified Community Expert]

I'm not convinced the nitrate is high. Are there fish in this tank and are you feeding them? If not, I'd remeasure nitrite.

Aquaforest does not mean that you should only dose 0.5 dKh per day. They mean you should only raise it by that much as you raise it to approach your target. If your tank uses 0.5 dKH per day, and you dose 1 dKh per day, alk will rise by their recommended limit of 0.5 dKH per day.

 

[Frans1992]

I'm not convinced the nitrate is high. Are there fish in this tank and are you feeding them? If not, I'd remeasure nitrite.

Aquaforest does not mean that you should only dose 0.5 dKh per day. They mean you should only raise it by that much as you raise it to approach your target. If your tank uses 0.5 dKH per day, and you dose 1 dKh per day, alk will rise by their recommended limit of 0.5 dKH per day.

There are fish inside the tank, but I already measure high nitrates before I put the fish in. I tested a few days like you could see in the chart. Maybe there are tiny amounts of nitrite in the water that doesn't show on the salifert test.

 

[Randy Holmes-Farley Verified Community Expert]

Can you post a picture of the tank?

 

[Frans1992]

Can you post a picture of the tank?

 

[Randy Holmes-Farley Verified Community Expert]

Ok, the alk is likely just binding to the rock and sand and there’s no great need to keep dosing it. Have you measured phosphate? You do not want low nutrients out of concern for dinos.

 

[Frans1992]

Ok, the alk is likely just binding to the rock and sand and there’s no great need to keep dosing it. Have you measured phosphate? You do not want low nutrients out of concern for dinos.

How do you mean that? If I don't dose anymore it will go under 7 dKH (alkalinity)

 

[Troylee]

How do you mean that? If I don't dose anymore it will go under 7 dKH (alkalinity)

Which is fine until you have an established tank with corals.. fish don’t care about alkalinity.

 

[Randy Holmes-Farley Verified Community Expert]

Agreed. There's nothing there that cares much about alk.

 

[Frans1992]

Which is fine until you have an established tank with corals.. fish don’t care about alkalinity.

Agreed. There's nothing there that cares much about alk.

Thanks for the help. But I'm planning to put some corals in later and wanna get al parameters good now. I messured phospate with my hanna checker it's at 0.00 now. How can I best raise this? I feed the two clownfish with frozen food mostly. Can it be the rocks are absorbing po4. I remember from my tank before I added po4 from aquaforest for a long time to raise it above 0.00.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks for the help. But I'm planning to put some corals in later and wanna get al parameters good now. I messured phospate with my hanna checker it's at 0.00 now. How can I best raise this? I feed the two clownfish with frozen food mostly. Can it be the rocks are absorbing po4. I remember from my tank before I added po4 from aquaforest for a long time to raise it above 0.00.

Feeding them more is easiest. Even if they do not eat every bit, that is fine.

With that much new bare calcium carbonate, dosing food grade sodium phosphate might be a suitable plan.