How many different types of algea effect tanks and corals negitivly and what are there names if there is not to many

Ehh....I wouldn't say any of them are negative. They just show different problems that are already present. For example: Red Slime, its a bacterial alga that grows well in poor lighting/slow flow/lots of nutrients. Well if your running a seahorse tank......its expected........in a reef tank full of SPS....red slime means you need a lot more flow.......better quality light....and you better figure a way to get those phosphates down.....or your sps will never grow. Hair algae......excess Phosphates.....even if your test kits come out 0. IMO.....algae tells you what your doing wrong....and when you see whats going on....you can fix it much easier.

I would add flow, vac your sand bed to remove as much as possible and add some phosphate media. The phosphate media will starve it out, its going to take at least a week or two, but if you keep those phosphate pads clean, they will keep your tank clean. do you have a HOB filter? canister? sump? You just need to get the filter pad in a place it will receive a lot of flow and clean out your water.You can also run it in a filter bag if you want.....heres a link to some of what im talking about. This will be your best way to erradicate quickly.

http://www.marinedepot.com/Seachem_Phos ... 55-vi.html

I would also siphon out the red/green slime directly while doing a water change, this will also help. I had red slime for months when I first set up my tank. Just have to watch nutrients in and out. :)

Keep that up, siphon out the slime directly. Every time you see it pop up enough to siphon it out.............water change. That will help you a whole lot.