emerald crab, I have a 180g display tank. With about 40g of water in my sump, I have 150lbs of live rock in my display, so usually when I dose I do so for 160g of actual water.

I am using the Fluval Carbon, I buy it in the 1650g container, the lable is stateing it's a low-ash carbon, and I consider it to be a fine granual with the pieces being in the 3mm range.

Does anyone run carbon and chemi-pure elite? Or just one or the other

Obviously replacement relates to volumes (tank/reactor) and what the water is actually like. I also monthly but just because. I'm not aware of any way available to us to detect when it's depleted. Is there a way?

I'm running RowaPhos, Chemi-Pure Elite, AND Carbon. Although I'm doing the tango with GHA, and so far I think I'm winning with the aid of a Seahare. :lol:

I think if you notice a color difference in your tank water when you change your carbon or do a water change you've gone too long.

If you notice color difference in your tank.... you have more of a water change issue.

Carbon is not a replacement for clean water.

I Don't if thats totally correct as I have been doing a 25% every Saturday for the last two months, Now as for the carbon, this is the first time I have used it in this setup which has been up now for 20 months.

There is a test that reads UV transmittance through seawater. You read the DOC before and after the carbon filter.

Myself, like the rest of us, don't bother with some expensive test. I change it every 4 to 6 weeks.

Not sure what you are saying.

You have yellow water???