What is this brown growth on my rocks ?

[DeepakNZReefer]

Hi Everyone,

I have a new waterbox system which is only about 2 months old. I have started the system with dry rock and dry sand. The tank is fully cycles and following are my parameters:

Nitrate: 64.3ppm
Phosphates: 0.135ppm
PH: 8.25
Salinity: 34.8ppt

In the past week I have been noticing some brown stuff growing on my rocks. I do not have lights on yet. The growth is only on the side of the tank where it catches some direct sunlight for like an hour in the evening. Should I do anything about it ? Or is it just part of the process ?

 

[SaltyCrew4u]

Question? How do you know it's cycled? Also nitrates at 64? Very high. What did you use to cycle if you used dry everything? Do you have other parameters checked?

 

[DeepakNZReefer]

Question? How do you know it's cycled? Also nitrates at 64? Very high. What did you use to cycle if you used dry everything? Do you have other parameters checked?

Ammonia is 0 or under 0.25ppm and I have fish in it already with constant feeding and every week the ammonia stays at the level I mentioned and nitrates keeps climbing up. I did a 30% water change today and tested nitrates after that which read 37ppm. I am intending to do another similar water change in another 3 days or so. I haven’t tested alkalinity or any other parameters I didn’t mention above.

I used fauna marine Bacto blend for cycling.

 

[gbroadbridge]

Hi Everyone,

I have a new waterbox system which is only about 2 months old. I have started the system with dry rock and dry sand. The tank is fully cycles and following are my parameters:

Nitrate: 64.3ppm
Phosphates: 0.135ppm
PH: 8.25
Salinity: 34.8ppt

In the past week I have been noticing some brown stuff growing on my rocks. I do not have lights on yet. The growth is only on the side of the tank where it catches some direct sunlight for like an hour in the evening. Should I do anything about it ? Or is it just part of the process ?

These are likely to be diatoms which are harmless and part of the tank cycling process.

Your nitrate and phosphate levels are fine where they are at the moment and will begin to stabilise as the tank continues to cycle biologically.

I'd just keep up with weekly water changes - are you running a protein skimmer?

 

[SaltyCrew4u]

Ammonia is 0 or under 0.25ppm and I have fish in it already with constant feeding and every week the ammonia stays at the level I mentioned and nitrates keeps climbing up. I did a 30% water change today and tested nitrates after that which read 37ppm. I am intending to do another similar water change in another 3 days or so. I haven’t tested alkalinity or any other parameters I didn’t mention above.

I used fauna marine Bacto blend for cycling.

Gotcha, I'm no expert by any means. But nitrates at the level are a little high .10-.30 is ideal IMO. Like mentioned above, its still a new tank. Like you mentioned, the browning is likely due to the light hitting it. Just wait until you add lights...

 

[DeepakNZReefer]

These are likely to be diatoms which are harmless and part of the tank cycling process.

Your nitrate and phosphate levels are fine where they are at the moment and will begin to stabilise as the tank continues to cycle biologically.

I'd just keep up with weekly water changes - are you running a protein skimmer?

Not running a skimmer yet, which I believe is part of the reason for high nitrates. I change out my filter socks every 2-3 days to manage the waste produced in the tank.

 

[gbroadbridge]

Not running a skimmer yet, which I believe is part of the reason for high nitrates. I change out my filter socks every 2-3 days to manage the waste produced in the tank.

That's right - when you run a skimmer some waste products are removed before they have time to be biologically converted into Nitrate - once you start the skimmer up the number will stabilise and water changes will help keep it in check.

In the medium term you want to aim for Nitrate 10-25ppm, and phosphate around 0.10ppm.
Once the tank matures (>12 months) you could drop them a little but higher is better than lower initially.

 

[DeepakNZReefer]

Got it! Do I have to wait till nitrates is between 10 to 25 before I add lights ? I am waiting for the skimmer to be in country which won’t be till March. I could add the lights before that if it’s not gonna make things worse in my tank.

 

[SaltyCrew4u]

Got it! Do I have to wait till nitrates is between 10 to 25 before I add lights ? I am waiting for the skimmer to be in country which won’t be till March. I could add the lights before that if it’s not gonna make things worse in my tank.

What skimmer is on backorder that long? You can add lights at any point. But know once you do, you'll have crazy unwanted growth.

 

[DeepakNZReefer]

What skimmer is on backorder that long? You can add lights at any point. But know once you do, you'll have crazy unwanted growth.

Octo elite 150s. They are all sold out in NewZealand.

 

[gbroadbridge]

Got it! Do I have to wait till nitrates is between 10 to 25 before I add lights ? I am waiting for the skimmer to be in country which won’t be till March. I could add the lights before that if it’s not gonna make things worse in my tank.

Part of tank cycling are ugly stages which is when you will almost certainly get unwanted algae growth.
Adding light will fuel that.

When you add light you would want to start adding Clean up Crew, like snails and also other herbivores.
If you build up the herbivores as needed you can keep algae mostly under control.
But you also don't want to add too many, too fast or you will starve them.

I had about 25 snails in my 75g (300l) tank when I was starting it up, some folks have more.

You can't avoid the ugly stages, unfortunately - but don't let that stop you adding some easy coral which will help consume some Nitrates and Phosphates. I wouldn't add more light than is necessary for coral health early on.

 

[DeepakNZReefer]

Part of tank cycling are ugly stages which is when you will almost certainly get unwanted algae growth.
Adding light will fuel that.

When you add light you would want to start adding Clean up Crew, like snails and also other herbivores.
If you build up the herbivores as needed you can keep algae mostly under control.
But you also don't want to add too many, too fast or you will starve them.

I had about 25 snails in my 75g (300l) tank when I was starting it up, some folks have more.

You can't avoid the ugly stages, unfortunately - but don't let that stop you adding some easy coral which will help consume some Nitrates and Phosphates. I wouldn't add more light than is necessary for coral health early on.

Sounds good. Thanks for that.

 

[Garf]

Sounds good. Thanks for that.

If you've got any nitrite detectable, that will artificially increase your nitrate result.

 

[DeepakNZReefer]

If you've got any nitrite detectable, that will artificially increase your nitrate result.

interesting, I have been testing nitrite while the tank was cycling (atleast I thought it was) and it was 0 always. I was using the API test kit. I haven’t bothered to test it after that. I will test that and see what I get this time.

 

[Paul B]

It's normal and natural, don't add or remove anything. If you didn't get that on the rocks, then something would be wrong. Don't worry about it.