brown stuff on my sand

I wouldn't add the salt directly to the water. Mix it with water first and then add it to a high flow area. I used to have a bad nitrate problem. One day I decided to take out the bioballs, filter, etc.. make it a little simpler you know.. And I did 20% water changes once a week.. I still do. You should be doing them at leasttt every other week, if not weekly. The nitrates went way down. If you tell me what you are using on your tank maybe I can help. Here is a pic of my tank when it finished cycling...


From Right to Left... Dead Snail, Empty Hermit Crab Shell, Hermit Crab in Snail Shell
+ diatoms

Is this what yours looks like

 

no i havnt been adding saltwater directly i mix it in a separate bucket i have and add it right where my filter returns the water. yeah it looks like that dead snail empty shell and hermit crabs and then the diatoms. i did my first water change a few days ago and one thing i didnt know was that when i change water i have to use salt water not freshwater i didnt think right :-( i know when it evaporates you use freshwater. so i thought the same. so thats why i have lower salt level. what do you want me to tell you about my tank ill gladly tell you anything to get it going properly. thanks