Algae problems

Question
Ever since I switched to the compact lighting system for my 20 gallon tank, I've had a plague of red algea (had some of that earlier). I got some medicine for that red algae, I think about $15.00 it cost. Now it has turned black! I cleaned out the tank and scrubbed the corals (not live) to get most of it off, then got most off the sides of the tank. It was also all over the floor of the aquarium ON the sand! My clownfish don't know what to do with it  and my shrimp and crab don't either. They won't eat it.

It is growing back, but I can't do this type of heavy duty cleaning every week. It's too much as I have other aquariums and I'm a very busy person besides. Got other pets and family so I need to SAVE time on this one. Got help?

I sure do appreciate any tips on this one. By the way, that black stuff is too heavy to effectively vacuum out unless it's in little bitty peices.

Thank you! :-)

Chris  

Answer
Chris,
Sorry for the delay in getting a reply to you.  The Experts site had this question listed as answered and then I took a closer look and saw that I hadn't.

Red algae is a bacterial algae.  Using the Red Slime Remover can help, but if you don't kill all of the algae then you start to grow a strain that is immune to the anti-bacterial medication in the product.

My recommendation is to take a sample of water to your local fish store and have them test it.  Specifically I'd be interested in nitrates and phosphates.  Both are know organic algae fertilizers and occur naturally in the water.

The easiest way to remove both of these is to do a good water change making sure to dig around in the gravel to remove waste.  When doing this water change you don't want to remove more than 30% of the water.  Make sure to use reverse osmosis water to fill the tank back up.  The easiest way to find this is to buy it at a grocery store.  It's in the bottled water section and is listed as Drinking Water.

Make sure to use a buffer to get the new water's pH up to 8.2 and obviously mix your salt in before adding the new water to your tank.

Remove as much of the algae from the tank as possible.  I recommend removing the decorations and soaking them in a bleach water solution.  The clorine in the bleach will kill all of the algae.  Once the algae is gone, put the decorations in fresh water and add some declorinating "Tap Water Purifier" chemical to the water.  After several hours smell the corals for bleach.  Do not replace them in the tank if they smell like clorine still.

Stirring the gravel up from time to time prevents a lot of algae from growing as it prevents light exposure time.

Add a phosphate absorbing resin to your filter.  Two Little Fishies PhosBan is the best one on the market right now.

Add some Scarlet or Blue Legged Hermit Crabs to the tank to help eat some of the waste and algae in the tank.  They are good at keeping the gravel clean.

Cut back your lights for awhile.  At most your aquarium lights should only be on 9 to 10 hours.  If the tank is in a bright room I recommend closer to 8.  Regardless, cut your lights back to 6 to 8 hours to retard the algae growth.

I also recommend picking up a copy of Julian Sprung's Algae: A Problem Solver book.  It's a great resource for removing all types of algae and it's fairly inexpensive.  We carry it for around $10 on our online catalog.

Best of luck and please feel free to contact me with any other questions.

Regards,
Scott Johnson
Aquarium Crazy Fish
www.aquariumcrazyfish.com