On Sat, 31 Jul 2004 13:58:04 +0100, Stefano wrote:
The juwel compact filter has four compartments.
The first one is the thin blue sponge, then there is a gap, then the coarse
blue sponge, then another blue sponge and then carbons and a white layer on
top. Is this correct?

Yes. Oh, actually I'm not sure that compacts have two course blues.
My rekord 70 has just one of each course and fine blue, then carbon,
then white. I don't buy the white ones, I just use a blob of filter
floss - much cheaper!

Instead of having two coarse blue sponges I have a blue and a green.
Does this make any difference, i think the green coarse sponge is a nitrate
sponge.
It came with the kit and it puzzled me as the instructions only show blue
sponges.

They have had some special offers - buy a month's supply of the
other sponges, get a free nitrate sponge, etc.

I've had one and use it as the top of the two blues. It works
fine - but if you are still cycling its absorption of nitrates
(and nitrites and ammonia I wonder?) might disguise the results.
Basically I bought mine to see if it would reduce algae, but
left it in the filter after the "active" period as a normal
sponge since by then it will be populated with useful bacteria.

It didn't relieve the algae, btw.

Just use it if you want instead of a blue. No issue.
Your sponges are just things which mechanically filter big
lumps out of the water, and which home bacteria which naturally
take harmful nitrites and ammonia out of the water. As long as
what you use is inert and vaguelly appropriate, you could use
other stuff. For example cannister filters use a mix of sponges,
ceramic rings, filter floss, carbon granules... so it's not a
big issue!
--
Flash Wilson
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