Green algea bloom

[jtrheaume]

Hey all,
For the past week i have been having a problem with green algea growing on the glass. I clean it when i go to work and when i come home from lunch its all over the glass. same when i get home. I dont get much on the sand just the glass.

Can anyone tell me why this happens.

[GaryP]

High nutrients, especially phosphates.

[Ram_Puppy]

possibly a spectrum change on his bulbs as well? but Gary is right, phosphate is the fuel dejure for algae.

[jtrheaume]

So just water change? 10%?

[Ram_Puppy]

a water change will definately help, but it won't solve the problem. Something is adding phosphate and probably other nutrients to your water that you can't test for.

I think a first step would be using a s power head to 'blow off' your rocks, siphon out as much as the gunk as you can (if there is any) and do a 10 to 20% water change.

Long term, you might want to invest in a phosban reactor.

Most importantly, you need to identify what is fueling the bloom. are you overfeeding? did a fish or invert die and is decaying in your rock structure some where? have you let your maintenance slide? are your bulbs old?

[GaryP]

Water changes are actually a very inefficient way to reduce nutrients. I assume you don't have a refugium or macro algaes that will outcompete the film algae for nutrients. You may also want to take a look at your calcium and alkalinity to make sure you have enough for the coralline algaes that will compete for nutrients.

Lastly, you can use a phosphate absorber like phosban or phosguard to chemically remove the phosphates. If you aren't having hair, or other nuisance algae, problems the simplest solution may be to just buy a mag cleaner. Film algae is common in tanks that may have low phosphates. You may not want to reduce it to much more then where it already is. Corals and coralline algae need some phosphates too. I think some guys around here found that out the hard way when they tried to aggressively reduce phosphates and they ended up reducing the growth and color of their corals. In that case they went a little to far in reducing them.

[jtrheaume]

I Have a mag cleaner and have to clean it 2 - 3 times a day to keep the glass clear. I will go through the rocks and "Blow" them off while looking for any dead inhabitants. I know I need to do a water change anyway so i will probably do that too.