Have a nitrite spike and been changing water for the past 3 days (40%, 40% and 75% today) but its not helping a whole lot, still in the purple on the api master kit. Have 5 guppies in the 20 gallon tank. Other tests are near normal. Sorry cant post a picture dont have a working phone at the minute. Vacuumed the gravel today also. Running algone in the filter. Have 0 nitrates in my tap water. Should I change water again today or wait till tomorrow ?