Purple Spots

Btownexpress · 11/27/2012, 02:05 PM

A week ago i noticed a couple of purple spots showing up on my glass.

3 days ago they were getting bigger. So I did a huge water change 60 gallons.

It was only my rocks, now its on my glass. Its very hard to get off. Any ideas what it is?

I will be doing a larger water change again tonight.

Any advice would be greatly appreciated.

jp

TealCobra · 11/27/2012, 02:17 PM

Is it calcium based? If so it's most likely coralline algae. Not a bad thing. It's a sign that your calcium, alkalinity, and magnesium are within the proper ranges.

http://en.wikipedia.org/wiki/Coralline_algae

T-dub · 11/27/2012, 02:58 PM

Post a pic but I agree with TealCobra, if it's purple and crusty and hard to scrape off your glass it is more than likely a coralline algae. This is the good stuff. If it's soft and you can swish it off with your hand or is forming a mat on your rocks tha you can blow off it is more than likely cynobacteria. That's a different story. I'd wait on another water change until you get a positive ID. What are your parameters? How long has the tank been going?

danil · 11/27/2012, 03:20 PM

It's got to be coralline algae. Agree it's PITA on glass (or worse acrylic!) but it's very desirable on the rocks - it looks good and prevent other nasty growing. If you have a reef tank you should pay more attention to CA and Alk at this point since coralline algae consume a lot of it.

Btownexpress · 11/27/2012, 04:11 PM

I will take a pic tonight,

Its vary hard to get off the glass, its not soft at all.

Parameters were good 3 days ago, i will check again tonight.

It is a reef tank, not much in it yet. And it has been running for 10 months.

jp

SweetTang · 11/27/2012, 04:22 PM

Coraline algae...no amount of water changes will stop it. Like others said, it is a good thing...it means your tank is stable and your water parameters are in a good place. Cheers!

rsaha · 11/28/2012, 12:49 PM

Get a blade style cleaner for your glass. Probably one with a handle that will let you get to the bottom of the back of your tank. Comes off easy with a blade.

Sugar Magnolia · 11/28/2012, 02:19 PM

Kent scrapers work well.

Barro777 · 11/28/2012, 05:03 PM

Credit card works for me.

atomicpile · 11/28/2012, 05:03 PM

I like to use an old credit card to scrape it off.

11/27/2012, 02:05 PM	#1
Btownexpress Registered Member Join Date: May 2012 Location: Btown, Minnesota Posts: 29	Purple Spots A week ago i noticed a couple of purple spots showing up on my glass. 3 days ago they were getting bigger. So I did a huge water change 60 gallons. It was only my rocks, now its on my glass. Its very hard to get off. Any ideas what it is? I will be doing a larger water change again tonight. Any advice would be greatly appreciated. jp

11/27/2012, 02:17 PM	#2
TealCobra Registered Member Join Date: Jul 2003 Location: McKinney, TX Posts: 896	Is it calcium based? If so it's most likely coralline algae. Not a bad thing. It's a sign that your calcium, alkalinity, and magnesium are within the proper ranges. http://en.wikipedia.org/wiki/Coralline_algae __________________ Matt Current Tank Info: 300g Marineland DD Reef Tank

11/28/2012, 02:19 PM	#8
Sugar Magnolia Registered Member Join Date: Feb 2003 Location: Northern VA Posts: 17,691	Kent scrapers work well. __________________ Adrienne The only thing to fear is fear itself....and spiders.

11/27/2012, 02:58 PM	#3
T-dub Registered Member Join Date: Oct 2010 Location: Marshall, MN Posts: 214	Post a pic but I agree with TealCobra, if it's purple and crusty and hard to scrape off your glass it is more than likely a coralline algae. This is the good stuff. If it's soft and you can swish it off with your hand or is forming a mat on your rocks tha you can blow off it is more than likely cynobacteria. That's a different story. I'd wait on another water change until you get a positive ID. What are your parameters? How long has the tank been going?

11/27/2012, 03:20 PM	#4
danil Registered Member Join Date: Jan 2011 Location: Concord, CA Posts: 935	It's got to be coralline algae. Agree it's PITA on glass (or worse acrylic!) but it's very desirable on the rocks - it looks good and prevent other nasty growing. If you have a reef tank you should pay more attention to CA and Alk at this point since coralline algae consume a lot of it.

11/27/2012, 04:11 PM	#5
Btownexpress Registered Member Join Date: May 2012 Location: Btown, Minnesota Posts: 29	I will take a pic tonight, Its vary hard to get off the glass, its not soft at all. Parameters were good 3 days ago, i will check again tonight. It is a reef tank, not much in it yet. And it has been running for 10 months. jp

11/27/2012, 04:22 PM	#6
SweetTang Registered Member Join Date: Feb 2012 Posts: 198	Coraline algae...no amount of water changes will stop it. Like others said, it is a good thing...it means your tank is stable and your water parameters are in a good place. Cheers!

11/28/2012, 12:49 PM	#7
rsaha Registered Member Join Date: Sep 2009 Location: Ottawa, Canada Posts: 587	Get a blade style cleaner for your glass. Probably one with a handle that will let you get to the bottom of the back of your tank. Comes off easy with a blade.

11/28/2012, 05:03 PM	#9
Barro777 Registered Member Join Date: Dec 2011 Location: Greenville, SC Posts: 173	Credit card works for me.

11/28/2012, 05:03 PM	#10
atomicpile Registered Member Join Date: Aug 2007 Location: CA Posts: 32	I like to use an old credit card to scrape it off.