Corals dying?is this algae problem

[Zebrazim]

Hi, maybe you could help me. My partner, who's tank it is, is away and over the past week there seems to have been an abundance of what I think is red coralline. Over the last few nights it has covered a what was healthy suncoral, 2 heads of a trumpet coral, some pretty little violet flowers?what they're called and is working it's way through heads on a polyp. He'll be gutted when he returns - any ideas of what could be causing this?

I don't know alot about the tank but I'll tell you what I do know - here goes - it's 200L.
It has 2 white tube lights and one flouressent tube all of which are on a timer. It's temperature appears to be within noramal limits - the green bit! - there's no substrate, there's a protein skimmer which I've been cleaning out daily, there are 4 jet things making a current ?proper name for these, all the rock is live rock, there are 5 fish, 2 clowns, a yellow tang, a cardinal and a regal tang - none are massive, also a shrimp and banded starfish, one massive turbo snail, several small ones and lots of crabs(mostly blue legged), loads of coral hard and soft - 2 anenomoes- both look well, a brain - looks great, a cataphilia, a leather mushroom, 3 different hammers, some yellow polyps, green button polyp, a plate with zoo on, zenia(several types one which is spreading like mad and although very pretty wish it wasn't there now!), another zoo. There may be other stuff I've forgot. There's also some kind of filter that I think takes phosphate out of the water and carbon (the carbon remover isn't always in it but I think it is at the moment.
He does a water change of 10% every 3-4 weeks I think. We feed them once a day with a variety of stuff - some target feeding with mysis, red stuff?, muscles. Seaweed sometimes, frozen blocks of all sorts, marine snow - it varies.
He set hetank up last October having got it from someone who was moving and needed to get rid.
I don't know what all the chemical tests are right now - they're usually ok - the calcium for an unknown reason always seems to be on the high side.
He adds trace elements as and when. There are several testing kits around so I can test for anything specific you suggest.
Sorry the info. is not very technical - as I say it's not my tank.
Hope someone can advice me.

Helen

[Scouter Steve]

To make sure this is red corraline, take a turkey baster and try to blow/suck it up. If it blows away at all try and suck it all up out of the tank.

[lcstorc]

Sounds much more like cyano than corraline. Corraline generally grows more slowly. Is the algae soft or hard. If it is soft and slimey then it is cyano. Pull as much of it out of the tank as you can. Did he leave you prepared amounts of food? If not, you are probably overfeeding. (Most common mistake in the hobby.) Try removing as much as you can and cut back on the feedings and it should start improving. It won't go away overnight but the more you remove the faster it will be gonel. You can use a turkey baster, a net, or even just your hands to remove it. Sometimes it helps to use the baster to get it off of the rocks and then scoop it up with a net.
HTH.

[Zebrazim]

I'll try this now and let you know later. Thanks

Helen

[Zebrazim]

Thanks for the advice - I'll try removing it and let you know how I get on.

Helen

[Woodstock]

If it is a slimey dark algae, it is cyanobacteria and can quickly smother corals. It can grow very guickly with the right conditions (low flow, phosphates and nitrates).
Since it is not your tank, you probably should not perform a water change but you can blow the algae off of the corals/rocks and then remove it with a fish net. Doing this will help export some of the nutrients out of the water.

The tank owner should increase the water changes (using ro/di filtered water), replace the phosphate removing media, reduce feedings, increase water flow rate, and possibly reduce the bioload (fish).