How To Get Rid Of Hair Algae With API Algae Fix

Hair Algae on PlantClose-Up of Hair Algae

I got hit by some hair algae (see image) after a plant trade not too long ago. This particular string algae is very soft and I can't feel when I pinch it between my fingers. I understand there's another variety of “string algae” out there that is strong and you can tug it or twirl it around using a toothbrush without it breaking.

The initial research I did suggested that I was in for a long and arduous clean-up effort including pulling out plants and cleaning them. Luckily, Tom Barr from the suggested using API AlgaeFix and so I did.

First up, I didn't find AlgaeFix at stores in my area. I had to order it from Amazon. Once I got it, I used the recommended dose on one of my tanks. The first dose didn't have a noticeable impact. The second dose seemed to weaken the hair algae. The third dose completely eradicated the hair algae from my tank. I didn't even have to clean-up leftovers — it was just completely gone. That's an amazing result for just 9 days.

I repeated the process on a second tank and got the same result. I also tried it in a small container with plant cuttings and noticed the same results using a stronger dose over a shorter period of time.

The label warns against using AlgaeFix with crustaceans and I can confirm that I lost a few shrimp when using it. None of my fish seemed affected. I had a nerite snail die during the period where I was dosing, but I'm not sure if it was a coincidence.

It has been several weeks and the hair algae hasn't returned in one of my tanks so I'm calling it a success there. In my second tank I noticed a few strands reappearing several weeks later so I tried another 2 doses over 6 days, but this time I used half the amount. This modification worked, but I still lost a fully grown Amano shrimp.

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  1. Is it safe to use after I put a dechlorinator in my koi pond? I have a 7000 gal pond.

  2. Good idea. I may just give that a try. Can't hurt and maybe it'll work on at least one of the species I'm having issues with.

  3. Thank you for such a quick reply. At least it isn't based on copper sulfate, but I'll have to look up the ingredient and see about any other possible toxicity.

    I'd give a lot for a solution to one alga I've been struggling with. It's an unknown species that's seriously ugly. ( I assume it arrived with a plant). All I know for certain is that it's not Black Brush.

    But it's such a dark green it looks black and strongly resembles a tangle of heavy sewing thread or maybe dying plant roots. Very soft textured, it grows near the surface and seems to prefer the long narrow leaves of H. angustifolia & Cyperus helferi. Physical removal of affected leaves is the only way to manage it as none of the Hygro species will tolerate being dipped and dipping just one plant and not the other makes no sense to me.

    The same tank also has a touch of a bright green fuzzy alga, that looks like tufts of green felt, or maybe filter floss (if it were green, that is ).

    I keep a lot of Nerite snails and filter feeding shrimp which are the reasons why I haven't tried any copper sulfate based algae remedies. Have to think about this product, I don't think I'd be comfortable risking the shrimp or the snails.

    • While the first dose of AlgaeFix doesn't seem to have any noticeable impact, the second dose does. So in 4-5 days you would know if it's going to work with the algae you have. You could use this to test a plant in a separate container. At least then you'd have an idea if it's worth trying to remove your shrimp/snails from the tank.

      I do know that this isn't a fix for all algae. For example, it doesn't do a thing against BBA which is what I continue to get patches of. Only hydrogen peroxide works against for BBA for me, but it requires spot treatment which means I have to wait for a patch to appear before I can attack it i.e. I win battles, but not that war.

  4. What is the active ingredient in this product ?

    • According to the bottle the active ingredient is:

      Poly[oxyethylene(dimethylimino)ethylene(dimethylimino)ethylene dichloride]: 4.5%

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