Green Hair Algae - Stephen Hopple


New member
So many questions, but I'll start here.

First, thanks for the writeup.

Second, please elaborate on what test kits were measuring inadequately, and which you now use.
Hi petes97,

Thanks for the comment. Actually I'm not certain that it was an issue with this kit vs. that kit, but an old kit vs. a new one. The old kit was an API kit from about 2004. The two new kits I got were the same API and a salifert. Both seem to read reasonably close to one another. These tests were done during the rock cook stage and were very easy. I still suspect that there was some inaccuracy, but not as much as testing water out of the tank.

Hope that helps;)

Your examination of your system is spot on. For me personally, there are at least 2 rocks in my system that hair algae loves. My thought is that these 2 rocks must be leaching phosphates that the other rocks and system as a whole don't possess. Great article.
Thanks for the comments fierceseaman!

I hope you get yours squared away. Many options are available, just find the one or combination of options that works for your system:thumbsup:
Im so sorry --New here.
Instead of replying on this thread I started a new one. I dont know how to fix or delete it.

Here is what I posted:
Thanks for this article. Ive been frustrated with hair algae for some time.Seriously thinking of trying this method but I have 3 questions:

1. Did you only do this on rock with no corals (ie mushrooms etc)
2. My phosphate tests always say zero-even salifert. So it would be hard to tell when the coohed rock is really clean. Would a month suffice?
3. I run rowasphos now . Only one reactor 250ml changed monthly. Should I up this? Do you still use rowasphos or another type?

135 g tank 100 lbs of live rock
Hi cindyreef,

Ultimately cooking the rocks is going to be a decision you have to make. It is a long and rather expensive process. I spent quite a bit in salt, although 30-40 gallons a week for ten weeks equates to just over 2 buckets of salt, it felt like more.

1. No I took all the corals off and left them in the tank. I had no mushrooms. I did have a few gorgs that made it through the cooking process.

2. When you cook the rocks, the algae dies and therefor the po4 is not taken up by the algae. You should be able to read a result with the kit in a few weeks. From reading various threads it seems that 2 months is about the minimum and I have read as long as five.

3. I actually switched from rowa to the granulated media due to cost. Not sure that there was that big of difference, although now I'm not afraid to switch out a large quantity;)
Sorry for all the questions but I have another,
I have alot of pink and purple coraline on my rocks. Would I lose the coraline during this process?
I really hope not but I suspect it will die too with no light.
You will lose some, but you will be surprised by how much remains. It also colors back up rather quickly afterwards;)
Nice article Hop.....

What are you doing now to "manage your sand bed"? I suppose this is the sand bed inside your display tank...

You mention that you change your phosphate media every two weeks... How much media is in each cylinder (reactor)?
Thanks Coralmex!

I really don't manage the sandbed at all now. After siphoning out the old sandbed, I ran it BB for about three months and then added enough sand for about 1" throughout the tank. The flow tends to pull it to two areas in the tank where it accumulates about 2.5-3". The day before every waterchange, I disperse it around the visible areas again and work on getting any of the crud that settled in it out. There really isn't that much though since usually it is lighter than the sand and is pulled across the sand, taken care of by the CUC or in a place where I can siphon it out at waterchange time.

Right now I run about 2 cups in each reactor. I'm thinking as time goes by I should be able to reduce the amount.

I'm still battling a couple spots of HA but they seem manageable right now;) It remains on one rock I couldn't cook because of the SPS mounted on it.
Roughly two months. I would have to look at the date on some pictures to be certain, but that is definitely within the ballpark;)
Hop, I should read some forums more often :rolleyes:
I just went thru the same thing. Mine started when I just didn't have time to work on the tank due to work load. That was last year and by January my tank was solid HA.
The three biggest changes that helped me were
1)Manual removal.............. constantly.
2)GFO, and lots of it.
3)A change in feeding habits.

A note on using GFO, don't expect miracles to happen for awhile if your overrun with HA. It takes time to work, but when it finally gets the upper hand, it makes manual removal so much easier. You finally feel like your winning the battle.

Nice article! :thumbsup:
Good points Ken! And thanks for the comments.

One important fact I learned this week is to keep up on the husbandry. I was too busy to do my typical 40 gallon weekly water change last week and my little remaining patches began to grow out again on the rock I didn't cook. So I'm working up a big batch of water for tomorrow and plan on manual removal and replace the GFO one week early;)

Thanks again!
Nice article!

I am going to cook my rock here starting in the next week or so

A couple of questions

Since the cooking is bacterial driven would it help to add a carbon source?

Also - is there any problem adding salt water from the display at the time of a water change - I know this isn't as clean as fresh saltwater but it would probably support the bacterial populations

Again thanks!
Thanks MO Will.

It was just easier to start with fresh water. The bacterial colony should stay well established and I wanted to ensure that I was using the best water I could. Since the tank water was obviously still loaded to some degree with the phosphates I wanted to push out, I elected to use 100% fresh SW. I'm not sure if anyone has done any side-by-side comparisons with the carbon and/or SW from the display. Ultimately I'm very satisfied with the way things worked.
Hop, see you like Schutzhund?!? Not many people are even aware of that this side of the pond, have a Schutzhund 2, Rott, he's getting old now though. You have a Shepard or Dobberman?

Anyways, good article. I think at a high level, there are no shortcuts. Cooking rock helps a lot, especially since most reef tanks have inorganic nutrients higher than the reefs (unless they are polluted). Also GFO, isn't a cure all as mentioned above, the main reason, IMHO, is that it works with mostly orthophosphates (inorganic), whereas the phosphate cycle is different, organic forms of phosphates can become inorganic and vice versa due to bacterial activity upon it....
I had a Shepherd and am currently without a dog(other than house pets and a pit/lab mix that I do obedience with). Our training group kind of shifted from schutzhund and began training bomb detection dogs for our troops over seas. So hopefully when the war settles down, we can start doing it again. But we still have a sch II dutchie in the group and a female GSD sch I. There are a few people in Denver we get with every once in a while and there are some great dogs of that side of the mountain;)

And thanks for the comments:thumbsup: I have to agree that there are no shortcuts!