1. hair algae: a fine green growth normally seen in a new tank but not in a mature one. Cause: phosphate excess, soaking out of rock and sand, or arriving via a non-ro/di water fill. Cure: GFO reactor, changing the medium once monthly until algae diminishes.
2. film algae: a green or brown film that adheres to glass. Normal and will sustain such fish as combtooth blennies, so don't take it out if blennies are your thing. Cause and cure: same as hair algae.
3. valonia, or bubble algae: usually a passing phase in a tank. Most visitors call it pretty. Tank owners call it a pest, but if you just let it alone, it will generally subside unless your tank is chemically out of hand with phosphates. Most everybody gets a few bubbles now and again. If it's epic, do your water changes with ro/di and check your phosphate level.
4. cyanobacteria --- a red sheet (with air bubbles as it gets thicker) ---is not an algae but a member of the archaia class, half animal, half plant. It's often a seasonal nuisance, a blush on the sand or a thick sheet draping rocks: it's all the same. For effective treatment, set your skimmer to wet skim, and turn out your lights for 3 days, going to a 4th day of low light to let things wake up. And do not black out your tank; room light is enough for the fish. Just no window light. You may have to do this once a month for several months to get it. It may also signal that your bulbs are burning down to useless.
5. macroalgaes with roots---never ever ever let one get started in your rockwork. If a rock shows green growth, set it dry in the sun until it dies. If you have sump/fuge, use cheatomorpha algae which does not have roots. Do not use caulerpa, especially grape caulerpa, which can get through pumps and spread to the main tank rockwork.
HTH.
2. film algae: a green or brown film that adheres to glass. Normal and will sustain such fish as combtooth blennies, so don't take it out if blennies are your thing. Cause and cure: same as hair algae.
3. valonia, or bubble algae: usually a passing phase in a tank. Most visitors call it pretty. Tank owners call it a pest, but if you just let it alone, it will generally subside unless your tank is chemically out of hand with phosphates. Most everybody gets a few bubbles now and again. If it's epic, do your water changes with ro/di and check your phosphate level.
4. cyanobacteria --- a red sheet (with air bubbles as it gets thicker) ---is not an algae but a member of the archaia class, half animal, half plant. It's often a seasonal nuisance, a blush on the sand or a thick sheet draping rocks: it's all the same. For effective treatment, set your skimmer to wet skim, and turn out your lights for 3 days, going to a 4th day of low light to let things wake up. And do not black out your tank; room light is enough for the fish. Just no window light. You may have to do this once a month for several months to get it. It may also signal that your bulbs are burning down to useless.
5. macroalgaes with roots---never ever ever let one get started in your rockwork. If a rock shows green growth, set it dry in the sun until it dies. If you have sump/fuge, use cheatomorpha algae which does not have roots. Do not use caulerpa, especially grape caulerpa, which can get through pumps and spread to the main tank rockwork.
HTH.