My tank i noticed has a fishy smell the last couple days.. Im starting to get brown algae on my plants and driftwood. I tested my water and i can never tell what my ammonia is at either .25 or 0. My PH is around 6.2ish, and my nitrates look between 10 and 20.. My nitrites are going up tho, my test kit is 3 years old but does seem to work as a few days ago i was at 0 and now its a like purple/pink color.. Its really hard to tell what its really at.. Here is a picture can you guys tell maybe ? and help me remove thi fishy smell.. I cleaned the rocks not only a week ago and i did a water change at that time too.. The filter isnt old maybe 2 weeks.