Killer Algae - Help!

[HTSL]

Hi - I thought I would post this to see if anyone can throw any light on the issue.

Over the last 6 months I have seen a growth of low lying brown/red algae growing on the live rock in areas of light. Before it starts to grow into threads it appears to be almost like a soft corraline type algae, red in coulur but soft to the touch.

Anyway, a while back I thought I would have a go at this algae and set to it with toothbrush etc. Half way through the process I noticed the fish starting to gasp for breath with most hiding. I immediately stopped however I lost my sailfin tang, hi-fin dottyback and 7 anthius! The symptons were gasping and then going into uncontrollable spins and immediatley dying.

I thought maybe a distubed a toxic sponge or something but last night, whilst carrying out a water change, I again disturbed this algae and lost a further 4 anthius.

What I cannot understand is my corals, mainly SPS/LPS are completely unaffected by this and continue to polyp and feed.

Has anyone experienced this before or anyone got some suggestions to get rid before I go for a complete strip down?

Many thanks in anticipation.

[landlord]

Things like algae, cyanobacteria (which I think you might have), etc, thrive in high nutrient environments. What kind of flow does your tank have? Describe your maintenance routines? Tank size?

[HTSL]

This is the confusing thing, I believe Im running a very low nutrient system, mainly SPS dominated. My flow comprises 10,000l turnover through bulkheads on the back with 2No. Stream 6100 each end of the tank. I dont think flow is an issue.

Size of tank is 5'6" x 28" x 28" however linked to that is another seahorse tank and a couple of algae tanks, total gallons approx 220g.

Ive only seen this algae in the last 6 months. I cant find it anywhere on the net nor in books. I bought a diadema urchin see if he would have a go at it but he just works his way around the stuff!

Ive been racking my brain to remember if Ive done anything different and nothing springs to mind.

My Nitrate is at approx 2ppm and phosphate less than 0.03ppm, almost undetectable.

[landlord]

How often are you changing your water? and in what quantity? Would you happen to have a picture of your tank or this algae in your tank?

[HTSL]

I change 10% per month. I'll try and get a decent photo later and post. Since I posted I have now lost 9 anthius and a fire fish!

[njdevilsfan]

chemi clean

[uscharalph]

Originally posted by HTSL
My Nitrate is at approx 2ppm and phosphate less than 0.03ppm, almost undetectable.

Your phospahetes are probably low because the algae is consuming them.

[ryan_paskadi]

remove the live rocks with the algae then clean them.

[HTSL]

Ive tried that and the algae leaves a residue which quickly grows back again. Also it is when I do this the fish start to suffer.

Ive just done a little more research and came up with this

http://books.google.com/books?id=SAd...FgC8#PPA237,M1

Sorry dont know how to condense the link!

[HTSL]

Just came back from the Plymouth Marine Laboratory who kindly offerred their assistance with the issue. They have comfirmed it is a toxic algae known as Trichodesmium, found in tropical, low nutrient, marine waters, mostly off the Carribean!

They had no known cure for this algae and couldn't really help with natural predators therefore i need to do a little more searching, although it looks like a full tank strip down is looking more likely.

[Craig Lambert]

HTSL...I wouldn't be so quick to assume a teardown is in order. Trichodesmium is a photosynthetic single cell cyanobacteria. I would look into whether or not this can be treated the same way as any other cyano outbreak. I would pose this question on the "Advanced" forum, and see what people say.

[Craig Lambert]

Here are two threads on cyano removal. Note what jdieck did with his tank:

http://archive.reefcentral.com/forum...what+did+again


http://archive.reefcentral.com/forum...ht=cyano+happy

[Frick-n-Frags]

you know. If I ever have the misfortune to get that crap, I believe it will portend the first time I ever do actually cook rocks in a chlorox bath.

gut reaction: immediately physically remove as much of that as I can find by removing the covered rocks

[HTSL]

Thanks Craig however my algae is a very tough type algae, not like the slime cyano they are talking about in the link. It cannot be removed by syphoning, blowing etc and I dont intend to disturb it for risk of further losses.

However, chemi-clean and red slime remover is not something Im familiar with over here, Ive have a search for nearest supplier

[hansmatt]

HTSL....I have what I think is likely the same algae. It does respond to lower lighting levels (put a rock in the sump, 2-3 day lights-off photoperiod). It helps, but did not get rid of it.