# How to grow green algae on rocks?



## SonicsDC25 (Jul 29, 2013)

I've seen various tanks on the forums that has green algae on their rocks and I absolutely love that color contrast. Does anyone know or have tips on how to grow that algae? Also, if I went to a lake and got one rock covered in green algae, what steps/precautions should I take to treat that rock before putting it into my tank? Or should that method of growing algae be avoided?

Thanks!


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## Michael_S (Aug 18, 2013)

I would not bring a rock from a lake that has algae on it. If there is any sunlight on the tank that can speed up the algae growing process and a healthy tank helps.


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## SonicsDC25 (Jul 29, 2013)

Thanks Michael, unfortunately my tank is in the corner of a room, so there's no direct sunlight


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## oyster dog (Jul 2, 2013)

I have two 65-watt power compacts over my 210 gallon (7' x 2' x 2') and I have a nice green coating of algae on my Texas holey rock. The lighting may sound low, but they are mounted in a very efficient reflector. They lights are on for 10 hours every day.

How is your tank lit?


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## SonicsDC25 (Jul 29, 2013)

I have 1 T8 17watt 50/50 coralife bulb :/ the ballast for the 2nd bulb is dead


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## oyster dog (Jul 2, 2013)

What are your tank dimensions? I have 130 watts over 14 square feet, or 9.3 watts/square foot.

I'd drop the 50/50 bulbs for 6700K or 10,000K bulbs. I use 10K. Bulbs.


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## SonicsDC25 (Jul 29, 2013)

My tank is only 30L x 20H x 12W.


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## oyster dog (Jul 2, 2013)

You currently have 17 watts over 2.5 square feet, or 6.8 watts/square foot. If you replace the other ballast you should be able to grow green algae with two bulbs.


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## SonicsDC25 (Jul 29, 2013)

I'll look into upgrading my light; however at the moment I see some brown spots on my glass. Is it brown algae and how would I stop them from coming back?


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## oyster dog (Jul 2, 2013)

Those are diatoms, and they will come back. They will also appear on your rocks, but will be supplanted by green algae after a few weeks.


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## SonicsDC25 (Jul 29, 2013)

Oh that's pretty cool! If these diatoms appear on my sand, do I just need to mix it around to get rid of it and should I scrub it off my glass tank? I like green algae, but on my rocks, not substrate and tank lol


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## notchback65 (Apr 3, 2013)

Here is my Texas Holey Rock,tank has been up and running for about 6 months.

















Not sure if this is the look you were after,I have my lights on for 8 hours a day(Coralife T5 HO)


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## SonicsDC25 (Jul 29, 2013)

Yeah I'm looking to get that green coat on my rocks, but more lush and full. Here are 2 pics of my rocks, they are somewhat brown now and I'm HOPING that they'll turn green =/


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## Iggy Newcastle (May 15, 2012)

The brown you have will get worse, and is common for new tanks(although I can never seem to get rid of it).

Stir your sand at water changes to avoid any settling on your substrate.


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## Love United (Sep 8, 2013)

Will brown algae become green algae? Is brown algae bad for the fish. I have a new tank and Demasoni and I just noticed brown algae.


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## DJRansome (Oct 29, 2005)

IME brown algae does not become green algae and it does not harm the fish.


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## SonicsDC25 (Jul 29, 2013)

Well I HOPE that it'll turn green, otherwise I'm just going to clean it off =/ Brown algae seems to be picking up in growth, at least on the 2 same rocks. The rest is still relatively the same. Been cleaning my glass more often as well due to the brown algae build-up O_O


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## JimA (Nov 7, 2009)

DJRansome said:


> IME brown algae does not become green algae and it does not harm the fish.


 I've had mine turn brown, then green and back to brown. Or maybe it's just the green growing over/on the brown? Right now I have a mix of both, seems to come and go but never goes away except where the BN pleaco and Tropheus have been busy.


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