one other thing, the way my powerhead is situated, it flows through the entire tank perfect, but gives very to no movement to the water surface. is this not good? or should i think about maybe something to move the surface a little?
As long as your pH is in line and you dont have a thick film of crud on the surface preventing light from penetrating downwards you should be fine.
Hair algae has very few requirements for growth. Really the big two are light and nutrients. Without one or the other it will eventually perish and since removing light from the tank will cause many other desireable organisms to depart our company, we have to concentrate on nutrients. Hair algae's main food as you probably know is phosphate. In the presence of phosphates, hair algae can and does easily gain a foothold on the aquarium. Once present, it will fix just about any new phosphates it can get its hairs on for added grwoth.
The next obvious question is how does phosphate get into my tank? Typically it is from food directly or from dissolved organic compounds from uneaten food that break down and release phosphorous groups. Feeding less or different foods to decrease phosphorous input is sometimes an option but again, we want to keep our fish alive and you are allready feeding very little. Another source for phosphates is from uneaten foods in the sand bed rotting away and releasing phosphate groups. And dont forget, once hair algae gets a foothold, it will remove free phosphates very quickly from the water column and will ususally keep free levels in the 0.1ppm or less range making it practically un-detectable by our test kits.
Were you to find some method (which to my knowledge doesnt exhist) that would selectively kill all hair algae your problem would still return. Remember, as the hair algae absorbs phosphorous from the water column it fixes it within its tissues, so killing it or having something else eat it does NOT remove the phosphorous, it just puts it in a different place. It is for this reason that a good quality phosphate remover is a requirement in tanks with even light or moderate fish loads to remove phosphorous from the water column.
Now your system is full of phosphate (either bound up in plant tissue, or sitting in the substrate) so I'd reccomend first, getting a good quality phosphate remover and putting it in say a very small HOB, even one sized appropriately for a nano if you like. I'm a big fan of rowaphos since it does not release phosphates back into the water column once spent, and it lasts a long time. Its a very fire-and-forget solutoin which is always best. After that, I'd reccomend getting started on substrate vaccuming every time you waterchange. This will help remove extra phosphates before they can get into the water column. Your final course of action could consist of a predator to "speed up" the process but remember, they just re-cycle the nutrient, a phosphate remover will still be required. There are a handful of hair algae predators each with their drawbacks:
Sea Hare - Eats great, will get stuck in powerheads without inlet foam and can over-predate and perish from lack of nutrients once their job is done
Sea Urchin - Eats great, also eats perhaps desireable coralline algae and can topple lightly-secured rockwork
Mexican Turbo Snail - Eats SLOWLY and can also topple rockwork
Lettuce Nudibranch - Eats SLOWLY and can also get stuck in a powerhead like sea hares
Algae Blenny - Eats great, but can over-predate, starve and die
Hectors Goby/Rainsford Goby - Eats slowly and can over-predate. Usually these guys also accept dried algae like nori though if you want to keep them.
So, in review, phopshate remover, gravel vac, and have faith. It took me a couple months to truly put an end to the hostilities in the great algal wars but eventually those methods won out. If I beat it, you can too
and one's going in my mantis nano tank. They can be fed with plain old seaweed for sushi, or you can spend the extra money and buy Nori. I'd just buy the cheapo stuff, most asian markets carry it.
