Hi there. First of all, thanks for all the advice up to now.
Last night I cleaned out as much hair Agra as possible using a toothbrush and my hands. That stuff stinks and is really slimy. That's where the fishy filter is coming from I'm sure.
I have done 3 phosphate tests. One of the tank water first thing before lights, one of the pre-salted 'clean' water from the LFS
and one of basic tap water just to get an idea of what was in there. I've also added a picture of just clear water to get a base level as I find it's hard to determine any accurate result.
Obviously, the darker one is tap water! Makes you think what's in that stuff!! The clear one is a base level (no test, clear). The other two are the used and clean marine water. They are very similar in colour so I think I can conclude that it's the water I'm buying that has the phosphates.
One thing to note. This is salted water so the marine salts do contain some phosphates in the mix. (correct?)
Now, are these levels too high, normal? Should I be worried?