Hello;
IMHO --- I have both fresh and salt tanks for over 30-years. I cannot believe what I hear about filtering! "My tank has no filter and it works fine --- I change 30% of the water a week"
WOW --- I change about 2-gallons in my Fluval when I change my filter floss and rinse out my prefilters in the lower basket once a week on my REEF!
You need a filter that filters and a nitrate sink like chaeto algae. The best filter in the world is a wet/dry with bio balls and the second is the UGF period. I use UGF's in all my tanks and my reef has the left 1/3 filtered by a UGF. The second filter in my tank is a Fluval canister, the third is a skimmer, and the fourth is a sump with Chaeto.
Get a good skimmer --- it removes waste before breakdown by the biological filters and reduces nitrates. Your filters are fine just rinse the media out once a week to remove larger waste to reduce nitrates. All filters that are working reduce waste to nitrate --- the best filters produce the most nitrate because they are the best at breaking down waste!
If live rock and deep sand beds really did all the work --- why change all that water? Just add lost nutrients, trace elements, and minerals!
Water changes are a poor substitute for a well set up system!
Try reading some of Reef Central's articles --- by Randy holmes Farley, etc. These writers are chemists and PHD's who know what they are doing and back it up with test data etc.
When it comes down to your tank you are the one who decides on the maintenance. I urge you to read all you can so you can make good decisions.
Enjoy!
