green algae

i suddenly have a massive amount of green algae on my glass and live rock. my tank is only 4 months old. i have only 5 corals, 15 lbs. of live rock and 2 fish. i just bought a new lighting system (coralife) last week. i also tried a powerhead, but it was blowing my hammerhead coral all over the place so i took the powerhead out. i do not have a skimmer. i feed my corals and fish mysis shrimp every other day. the algae started about 3 days ago. any ideas?

 

oh, i should add, i changed my water about 4 days ago with ro water after i had 2 fish strangely die.

 

The algae problem is probably a result of both your lighting(new) and excess nutrients in the pelagic(water column) area of your tank!
A water change will help...
Check your pH and alkalinity level to start!
Also, why can't you reposition the powerhead to afford your tank and it's inhabitants more water flow?

 

thank you, i will try a water change. also, i have moved the powerhead to several different positions in the tank and it still blows the corals around too much. my tank is only 20 gallons. are some powerheads too powerful for the smaller tanks? Can you also recommed a good skimmer for 20 gallon tank?

 

My hubby has a 20g tank, he uses the rio nano skimmer which works great and has a capartment for carbon. He also has the hydor koralia #1 in the tank. It has alot of flow but it's a wide angled flow that is gentle. He has in placed in one corner pointed towards the surface of the water, this still alows flow to get through all of the tank but it has not caused any damage to the corals. Do you do regular water changes, test your water?