Purple Film in Refugium

[J Codling]

Hi guys. I have a 15 gallon refugium piped into my 55 gallon FOWLR tank. I
also have a 30 gallon sump. The refugium is supplied from the sump thru a
powerhead. I've had the refugium setup for about 4 months and about 2 weeks
ago piped it into my main system. I have several macros and about 5 lbs
live rock in it. Prior to piping in the refugium my nitrates were off the
chart, around 100ppm. After about 2 weeks they have dropped to about 40ppm
which I am very happy with.

My question is, in the refugium I have seen a growth of a thin purple film
over the entire live rock. It breaks up very easily with a spoon or finger.
What is this stuff? I'm wondering if my flowrate is too low or should I
just let it grow? I have my refugium lit 24/7 with 45W (15daylight,
15actinic, 15 6500k).

Thanks in advance.

Jim

[PaulB]

Cyanobacteria I think.

..
"J Codling" > wrote in message
nk.net...
> Hi guys. I have a 15 gallon refugium piped into my 55 gallon FOWLR tank.
I
> also have a 30 gallon sump. The refugium is supplied from the sump thru a
> powerhead. I've had the refugium setup for about 4 months and about 2
weeks
> ago piped it into my main system. I have several macros and about 5 lbs
> live rock in it. Prior to piping in the refugium my nitrates were off the
> chart, around 100ppm. After about 2 weeks they have dropped to about
40ppm
> which I am very happy with.
>
> My question is, in the refugium I have seen a growth of a thin purple film
> over the entire live rock. It breaks up very easily with a spoon or
finger.
> What is this stuff? I'm wondering if my flowrate is too low or should I
> just let it grow? I have my refugium lit 24/7 with 45W (15daylight,
> 15actinic, 15 6500k).
>
> Thanks in advance.
>
> Jim
>
>
>