need help with my nitrates

[watchedout]

I am having a problem bringing my niterates down i have a 90 gal 20 gal sump a Reef Octopus NWB150 6? a 18 watt deep blue uv and around 120 pounds of live rock if not more about 2.5 in sand bed and chaeto in my sump and i cant seem to get the levels down. i dont know if i have to many fish or im having other issues i feel every other day flakes

 

[KathyC]

How many fish do you have and what kind are they?
How long has the tank been set up?
What is your water change schedule and how much do you change?
Are you running and/or GFO or carbon in reactors?


Let's start with those questions

 

[watchedout]

1 naso tang 1 lollipop tang 1 por puffer 1 clown trigger 1 blue thoat trigger 1 gold bar maroon clown and a diamond goby
tank has been up for 2 years more or less and and once every 3 weeks but i just did 2 with in a week and still nothing. im thinking if i should up grade my sump i dont know it is stressing me out and i change about 30 gallons

 

[Tonyscoots84]

How big is this tank?
Are you using Rodi water?
Are you running gfo and carbon in reactors?
What skimmer are you running?
What size water changes (in gallons) are you doing weekly/monthly?

 

[watchedout]

its 90 gal 20 gal sump a Reef Octopus NWB150 6? a 18 watt deep blue uv i do not have any reactors i use carbon i do 30 gallons every 3 weeks and no RODI water didnt think i need to with fish only