exploding algae growth

[wolleylabel]

ive had my tank running for about 2 months now....everything is goin well and all of sudden one afternoon ive noticed a incredible amount of algae growing...and it was neon green...should i be worried....its growing all over the front of the tank on the glass and some on the live rocks....it pretty cause i have all these colors but im a lil worried if this is normal or not...

 

[ChrisRD]

It's pretty normal to go through some algae cycles in the first 6 months or so of a new system. That said, algae is the result of nutrients + light, so if you haven't changed anything with your lighting, there's nutrients coming from somewhere...

This can happen in various ways, for example:
1. The water you're using for evaporation top-off and mixing-up water changes can be the source. This is the reason many experienced reefkeepers use RO/DI or other purified forms of freshwater.
2. Something(s) may have died-off in the system releasing nutrients as it decomposes. It's common for newer systems to have various lifeforms (some unseen) die-off of the live rock and live sand for a while, resulting in various algae cycles.
3. You may be adding it via food, additives, etc. Overfeeding or overdosing of nutrient rich additives, liquid foods, etc. are common reasons that many folks develop algae problems.
4. Lack of nutrient export - ie. you're not removing organics quickly enough from the system and they are accumulating.

Controlling algae problems basically boils down to finding a balance with limiting nutrient import, exporting excess nutrients and having some grazing animals to curtail any minor growths.

HTH