Safe nitrate levels in the water

[Stepod72]

Hi all,

Just after a bit of info in regards to nitrate levels.

I do a water change every weekend on all my racks, I clean sponge filters monthly and change the filter wool in the reef when it is no longer white. I have crushed coral and sand as substrate.

My ammonia and nitrite are on zero but the nitrate sits around 40 ppm.

Are my nitrate levels ok?

How high does the nitrate have to go before it's bad for the fish?

And if my nitrate is high, what are the best methods to get it down?

I understand that nitrate is produced by waiste and I generally try and keep the tanks clean and I don't over feed the fish.

Just interested to see what everyone does

Cheers,

Steve.

[zigzagfish]

Have you ever wondered what it really means for your aquarium to be "cycled"?

This is referring to natures Nitrogen Cycle.

Here is a quick break down for a better understanding:

The Nitrogen Cycle is natures way of purifying itself.

It is the process in which nature creates beneficial bacteria to break down waste.

Just as in nature, an aquarium environment needs to develop a Nitrogen Cycle as well.

This cycle will be what converts the toxic fish waste (fish excreta, urine, and old food) into a non toxic form and is what will keep your aquarium environment clean and healthy.

This a lengthy process and takes much patience.

Just What Does The Nitrogen Cycle Do Inside an Aquarium Environment?

The Nitrogen Cycle has 3 major steps inside an aquarium environment.

When testing the Nitrogen cycle with water test kits, we are reading the byproducts of the Nitrogen Cycle.

These byproducts are ammonia, nitrite, and nitrate.

Step #1: Ammonia (the byproduct of fish waste)

Fish excreta, urine, and old food pollute aquarium water. The decaying process of this waste creates ammonia which is very toxic to fish.

Step #2: Nitrite (the byproduct of Nitrosomonas Bacteria)

Nature creates a beneficial bacteria called Nitrosomonas Bacteria to break down the ammonia. The converted byproduct of this bacteria is called Nitrite which is still toxic to fish.

Step #3: Nitrate (the byproduct of Nitrobacter Bacteria)

Nature creates a beneficial bacteria called Nitrobacter Bacteria to break down the nitrite. The converted byproduct of this bacteria is called Nitrate which is not toxic to fish if kept at low levels.

In nature, Nitrate byproducts happen to be a food source for plants and algae.

In an aquarium environment, we would not be able to keep enough plants to consume all the nitrate; therefor, we preform partial water changes to remove this byproduct before it reaches toxic levels.

So, the "cycle" moves like this:

fish waste = ammonia (toxic to fish)

Nitrosomonas Bacteria = nitrite (toxic to fish)

Nitrobacter Bacteria = nitrate (not toxic to fish if maintained at low levels)

water change (to remove nitrate)

A "cycled" aquarium should read:

ammonia: 0ppm

nitrite: 0ppm

nitrate: ideal range .1ppm - 40ppm ,

Warning: nitrate levels should never exceed 75ppm - Exceeding this level is toxic to fish.

[Stepod72]

Spot on info thanks Lionel, I'll be of to get some stability to introduce more bacteria to let the nitrate cycle properly.

Very handy bit of information to have

Cheers.