Hi! Not sure why, but our 20gl tank has been doing well for 3 months. Then I decided to add a substrate and 10 plants. Fish still did well with all this change, plants growing as they should, water changes at 20% about every 2 weeks or as needed. Added 5 nerite snails, 4 amano shrimp, a couple of ghost shrimp. Water was clear. Then added a few more colorful plants that needed a CO2 booster, Plant fertilizer. Our water was so cloudy after 2 days you couldn't see the plants in back. So no fish, shrimp, snails lost (knock on wood) The levels are all within range, and 0 ammonia. But still cloudy. I did a 30% change yesterday and it did get a little clearer after a day. My numbers are all within range. When I change the filter I make sure to let the old filter drain water to new filter and submerge in the tank prior to adding to my Tetra whisper 20-40gl tnk filter. lights are timed for various times of day and turn off at night. What am I doing wrong?