Large Bug-eyed fantail gold fish and tank water

Question
I adopted large bug-eyed fan tail gold fish and feed it flake food.  It lives in a 10 gallon tank with water changes every two weeks and vacuumed gravel. The problem is cloudy water with a pink tinge.  I believe it's the food but don't know what to do food wise.  The fish is very healthy and happy and loves to eat. Please advise.  Thank you.

Answer
Feed it only twice per day... what it will eat in three minutes of time... You can also offer it brine shrimp. If you are feeding little red pellets or crisps they will tint the water.  Change 30% of the water once per week...Tetramin goldfish flakes are very good for your fish....  dave