Light is on about 12hrs/day.
Tank is only about 1 mth old and has 4 fish in it...2 opaline gouramis, 1 tiger barb and a rainbow shark. Been battling some ammonia and nitrate issues. Been doing 1/3 water changes once a week for the last 3 weeks.
I did change the filter that it came with originally so I probably messed up my cycle. I started with a topfin 40 and upgraded to a fluval 70 with the 3 stage filtration.
Is black brush algae bad? What should I do?
I agree with FishCr8zy about the lights. I would also suggest that you add more plants, I know it seems weird but the plants will compete with the algae for light, and nutrients which will help to slow its growth and eventually kill it. I recommend against snails because they prefer to eat plants over the algae so if you want an algae eater stick with shrimp or fish that won't eat your plants.
What would be a good type of snail?
Are there different shrimp types too, which is best if so?
Cherry shrimp are my favorite, because their so easy to keep and they can tell you before hand if there is something drastically wrong with your tank. As for snails, apple snails a very popular but they will eventually eat your plants. http://www.planetinverts.com/Red%20Cherry%20Shrimp.html
http://www.aquaticcommunity.com/inv/applesnail.php
Never seen one in this color, but apple snails come in many different color varieties the most common is yellow my, LFS sell them with black and yellow stripes, and in plain red.
I think I've got it going