Thanks for the positive replies
The blue sponge grew over everything. even corals with a powerful sting could not stop it. It did not grow at a great speed but after seven years of it being in the tank it had covered about a third of the rockwork. I had tried injecting it with acid which was quite effective but threw the pH and alkalinty way off. The sponge would manage to regrow from the tiniest speck of tissue.
I stripped the tank and used it as an opportunity to get rid of many of the huge soft corals that were dominating the tank.
There is only six yellows in there and I agree the tank is a bit small for them but they have been there a long time now and dont squabble at all.
I do have a pair of clowns for the magnifica. The video shows them getting ready to spawn. They do this every two weeks without fail. The female is fourteen years old now and still looks good.
Flow is provided by a tunze 6100 and a 6200 on a multi controller. In addition to this there are two return pipes from the sump each giving about 1000 litres/hour flow. Both of these are pointed at the anemones.
The dimensions of the tank are 1.85m long, 0.74m wide and 0.975m high plus a 4'x2'x2' sump.
I use a deltec AP703 skimmer and a korallin calcium reactor along with a homemade nitrate reactor which I use occasionaly. I am a little nervous of running it too much after speaking to Eric Borneman about how a bacterial monoculture can develop if they are run continuously.
Here is a picture of the tank with blue sponge before the rock was removed.
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