My nitrate over the last couple of months has been fairly low (on my 5 or so) but then suddenly over the last fortnight has been 40 (maybe even more - I find the scale hard to distinguish at these levels). I can’t particularly work out why - I haven’t added any more fish (there are 4 small fish - clowns, damsel, cardinalfish, a cleaner shrimp and a few snails in 200L which feels fairly lowly stocked), 10% weekly water changes, no change in feeding amount or volume. I’ve increased the water changes but I’m not sure I can continue to water change larger volumes (and feel that will get expensive with salt anyway). I’ve rinsed the canister material. The only thing I can put it down to is one fish sadly “vanished” overnight recently - I’ve searched for it from every angle but can’t see it so presume it died and provided an ammonia load (though it seemed fine the day before). Short of taking out the rock to look for it not sure what else I can do though!
There are a small handful of softies and LPS in the tank and most of them seem reasonably happy, a couple maybe not with quite the polyp extension that I saw when I purchased them.
(If you had to run a canister) what would you run in the canister? Live rock rubble rather than the biomedia/sponges?
I do apologise for the silly questions - I feel the learning curve from fresh to salt has been steep and constantly trying to do right by these creatures!