When will my dry rock turn live and purple?

cameronh21 · Feb 3, 2019

Hey everyone, I’ve been running my reef tank for a little over a month now. It is a Fluval evo 13.5 with a couple corals. I used dry rock to set it up and it is white right now. I was just wondering when or how long it will take to start to turn purple and start to grow coralline algae. Thanks!

tupes · Feb 3, 2019

Well, that all depends.

Did you start with live sand? If not, it will take some time. "Live" pretains to the bacteria that builds up on the rock. Copepods and amphipods you can buy them and dump on the tank to seed it.

Personally I started with dry rock and sand so.. I started my new tank in April 2018 and just seeing coraline on my glass and rocks.

Do you have a test kit and and are you testing? If so what are your parameters?

A month is kind of quick to be adding coral. Especially if your tank is not cycled and you go through the ugly stages then you will get disappointed thinking you did something wrong.

RamsReef · Feb 3, 2019

Half year / year

Katrina71 · Feb 3, 2019

Grab an empty shell with coralline on it and scratch it on your rock. I did it with my son's and it took about 2 months.

tupes · Feb 3, 2019

Katrina71 said:
Grab an empty shell with coralline on it and scratch it on your rock. I did it with my son's and it took about 2 months.

This is a way also. Seeding with coraline..

If this is done you need to make sure there are no aptasia or other unwanted pest that will get in to the tank during this process

When I started my tank, using dry rock and sand, anything that I buy coral I completely break the rock or frag plugs or cut the coral if I have to and glue it to a piece of dry rock then put it in the tank.

I have had to many bad experiences with bad hitchhikers

Katrina71 · Feb 3, 2019

He's right. There is a risk. Always a risk adding anything wet.

Captain Quint · Feb 3, 2019

Katrina71 said:
Grab an empty shell with coralline on it and scratch it on your rock. I did it with my son's and it took about 2 months.

+1 with the shell, coral plug, almost anything with C.A. encrusted on it. You'll need to make sure whatever you introduce does not contact with air or it will die off.

Put it in the tank and scrape some off to spread throughout your system.

@cameronh21 welcome to R2R too.

Captain Quint · Feb 3, 2019

Katrina71 said:
He's right. There is a risk. Always a risk adding anything wet.

I agree @tupes is correct on the risk.

lapin · Feb 3, 2019

Howdy and welcome

Your rock is live as soon as you add water. Bacteria will start to grow. You add light and more will grow. Add some coral and this adds more bacteria.
How long it will take to turn purple. This question as no answer. If a purple coraline strain is introduced there is no guarantee it will grow. If it does grow it might be on your glass and not the rock. In most tanks I have had with dry rock, it takes from 6 months to a year before I start to see it on the rock. Before this my rock has turned brown then green then red and back to green again before I see any purple.

jtl · Feb 3, 2019

With the right lighting and params figure a year.

cameronh21 · Feb 3, 2019

tupes said:
Well, that all depends.

Did you start with live sand? If not, it will take some time. "Live" pretains to the bacteria that builds up on the rock. Copepods and amphipods you can buy them and dump on the tank to seed it.

Personally I started with dry rock and sand so.. I started my new tank in April 2018 and just seeing coraline on my glass and rocks.

Do you have a test kit and and are you testing? If so what are your parameters?

A month is kind of quick to be adding coral. Especially if your tank is not cycled and you go through the ugly stages then you will get disappointed thinking you did something wrong.

I did start with live sand. I am testing with API test strips and all my water params are acceptable.

0 ammonia
0 nitrates
1.025 salinity

My tank got past it’s first brown algae outbreak with the help of some snails. And I only added Green Star Polyps and A Euphyllia torch and they are all doing amazing.

Thanks so much for your reply, it was very helpful!

cameronh21 · Feb 3, 2019

Katrina71 said:
Grab an empty shell with coralline on it and scratch it on your rock. I did it with my son's and it took about 2 months.

I have a purple rock with a mat of GSP on it. Will this also help spread the coralline algae?

cameronh21 · Feb 3, 2019

lapin said:
Howdy and welcome

Your rock is live as soon as you add water. Bacteria will start to grow. You add light and more will grow. Add some coral and this adds more bacteria.
How long it will take to turn purple. This question as no answer. If a purple coraline strain is introduced there is no guarantee it will grow. If it does grow it might be on your glass and not the rock. In most tanks I have had with dry rock, it takes from 6 months to a year before I start to see it on the rock. Before this my rock has turned brown then green then red and back to green again before I see any purple.

Thanks for the reply! I just made it past my first brown algae phase.

RamsReef · Feb 3, 2019

Just leave it lol, one day you will wake up and realize your whole tank is covered.

I wouldn't put effort into it.

cameronh21 · Feb 3, 2019

Ramasule said:
Just leave it lol, one day you will wake up and realize your whole tank is covered.

I wouldn't put effort into it.

Awesome, thanks so much for your help!

tupes · Feb 3, 2019

cameronh21 said:
I did start with live sand. I am testing with API test strips and all my water params are acceptable.

0 ammonia
0 nitrates
1.025 salinity

My tank got past it’s first brown algae outbreak with the help of some snails. And I only added Green Star Polyps and A Euphyllia torch and they are all doing amazing.

Thanks so much for your reply, it was very helpful!

This is good that you tested but you should eventually invest in a better test kit. ie. Salifert, RedSea or hanna instrument API isnt the most reliable. Just keep an eye on things keep up with water changes and you are going to see purple all over.

cameronh21 · Feb 3, 2019

tupes said:
This is good that you tested but you should eventually invest in a better test kit. ie. Salifert, RedSea or hanna instrument API isnt the most reliable. Just keep an eye on things keep up with water changes and you are going to see purple all over.

Thanks so much for the test kit suggestions. I am doing 2-3 water changes a month at this point. Thanks for all of the helpful replies