Algae is a function of light and nutrients, particularly Nitrogen. Reducing light or having competing light spin things in the right direction. Having algae eating fish, like Plecostomus, Mollys, and Otocynclus Cats also help. I've never used a CO2 Unit, but have read of conflicting opinions as to how helpful it was toward the end of having lush, green plants. I got the impression that it was a challenge keeping the natural cycle of photsynthesis and respiration in balance. Can you manually remove / scrape any of the algae? You could try setting up a small tank for temporary housing should you decide to clean the main tank thoroughly. I would try manually removing what you can and reducing the light a tad and see how it goes first.

I would not add any fertilizer [I assume your useing a liquid fertilizer]. The alge should slowly die off.

Once the plants start to fill in the tank, they will suck the nitrogen out of the water. This will then help reduce the algea. I agree with james ny, stop fertilizing till it starts to subside.


You may want to look into getting some type of hygrophilia just because they are extreamly fast growing plants and this will help suck the nutrients out of the water. Another good one that I have going out of control in my tank is Ceratopteris siliquosa. Very very fast growing. You will need about nutral water, +- 1/2 ph, for this one. One plant in my tank roots off medium floating replicas of it self about five times a month.


I replaced my substrate and boosted my lighting. I had a big algea bloom, it went away in about 2 weeks, in that time some of my plants doubled in size.

I would second the opinion about adding some fast growing plants like hygro, or even hornwort. They act like a nutrient sponge and can out compete the algae for nutrients until the other plants can catch up abit. Besides your swords, your selection is slower growing and is being out competed, possibly due to...

A. Too much light... I'm wondering if your halide is one bulb? or two? And also what the color temp is? 5Kish? 10 or even 20K? Those higher temperature bulbs are desinged for reef aquariums and are not so great for freshwater plants, except algae... of course. I'm also thinking your photoperiod is a tad bit too long, try cutting back to eight hours. Halide is very intense stuff!

Or B... I'm thinking you might have some junky water. I know that my local tap water, and many others, is very high in phosphates which is like miraclegro for algae. Before you jump into CO2, I would test your water for it and possibly consider a reverse osmosis/deionizer filter for your tap. I know it had made all the difference for me, and you have a source of healthy water for you as well!

CO2 can be tricky, and complicated... particularly in large tanks like yours. And with a wet/dry filter not really worth it- most of your co2 would dissapate through the filter.

Cheers

Many thanks to all for your replies. My husband was so impressed that he registered for GardenWeb himself. We have cleaned off all the existing algae, planted some additional plants, tested the water and reduced both the feeding of the fish and the plants. It's been a little over a week, no sign of any additional growth. Thanks again!