rmenkes":38qnui9y said:
I use tap water for changes which I've been doing for over a year now with no problems.
Your nitrate is over 160, I'd call that a problem! 8O As Danmhippo already said, get your tap checked for nitrate. Also check your water with a few other quality test kits and see if you're getting a true reading, occasionall when a reading is really ridiculous, something's up w/ the reagents.
Short term remedies for all that nitrate would include a series of good sized water changes with aged seawater mixed from purified water or trying one of the many nitrate removing resins, filters, etc.
Long term remedies would include purchasing a good ro/di unit, installing a refugium or 2 with large amounts of macroalgae, installing a deep live sand bed either in the main tank or in something else connected to it, and thinning out your fish population and/or reducing feedings. Aggressive protein skimming will do wonders also.
Questions:
1. How many fish and of what size are in this tank?
2. What and how much food are you feeding?
3. How big is this sohal? A 92g corner tank is about 4ft long at its longest point which is cramped for a sohal tang.
4. What kind of protein skimmer, if any, are you using?