Hey Ray,
Everyone is giving you good advice,
Let's try to determine WHAT is the root source of your nitrate problem though.
Controlling the problem is one thing, but actually eliminating the root source is another.
For about 6 months, I had 40ppm nitrates.
I used RO/DI water, had a skimmer, and did 10g per week changes in a 30g.
I kept the nitrates between 20-40ppm ALWAYS....
This was a bandaid obviously.
I took a hard look at my feeding.
I changed what I was doing and now I have 0ppm consistantly.
Rather than dumping the frozen cube of mysis into the tank, I pre-thaw with RO/DI.
I also only put a small amount in the tank at a time, just enough for the 4 fish to chomp on. If they finish, I put in a couple more pieces.
There is little to no leftover foods.
I also feed every other day (M-W-F) nothing on weekends but dosing phyto/cyclo.
I believe the excess food in the tank was causing my nitrate spikes.
See if you can investigate the root cause of your nitrate problems for a long-term solution.
Good Luck!