Red algae

Question
I have had this tank for 2 1/2 years for the last 6 months I have been getting this red dust on sand and rock?  I have tryed alge remover but has not worked  the only thig it has done has killed fish ! MyP H 4.8.  And salintiy is just right. How do I get ths red dust to stop.

Answer
Hi Lucas,

Your pH, should be between 8.1 to 8.4, I believe in your reply, you actually meant to write 8.4?

Since your aquarium has been running for 2 1/2 years, perhaps this outbreak could be partially caused by a shift in your lighting system. Check your lamps to see if they need replacing. For most Metal Halide's, Power Compact Fluorescents, and T5 Fluorescents you would want to change them at least once a year, with some hobbyists preferring to replace them twice a year.

You could also try a product called ChemiClean Red Slime Remover. See the following example link below for this product. http://www.ocreef.com/chemi-clean_red_slime_cynobacteria_remover_2_grams     

Also, make sure your nitrate levels are in check, as you know nitrate is fuel for nuisance algae and red slime bacteria. If necessary do a water change. Also aggressive protein skimming will help keep your DOC (dissolved organic compounds) levels down. If you don't have a protein skimmer, you may want to invest in one.

Also, if you're running a sump filter with bio-materials, it may be time to add more bio-materials, or give them a partial cleaning. Too much debris trapped from years of build-up can cause a spike in nitrate levels, fueling an algae outbreak.

I wish you luck with all your future saltwater aquarium endeavors.