Hi guys, so I recently got new fish for my 150G tank. I been testing the water with my API test kit, but my dumb self did not check the expiration date of the thing. So I went to the LFS, bought 7 new fish. (schooling fish, garibaldi and an angel fish). I acclimated them for like 4 hours. I was cleaning up and realized the Kit was expired, so I rushed to the LFS and bought a new kit. Needless to say results where different. While it says that everything else reads: Ammonia 0, Nitrires:0 and PH anywhere around 7.8-8.0 but im figuring its closer to 8 in the scale. However, the Nitrates are a whooping 180ppm. Im assuming they're higher since the color of the test tube was RED. This tank has been up and running for about 8 years now. However I did recently introduced a porcupine puffer, so i figured the bioload would be higher. Im going to cut down in feeding in the next weeks. Ive been feeding the puffer about 2 mysis shirmp cubes, and 1 emerald cube. (and sometimes just a bit of krill as candy). I feed the rest of the fish 2 cubes of mysis and 1 emerald as well. Total of 6 cubes a day. I have 6 Chromis, 5 Silver batfish (still about 2 inches)? (i forgot the name just now ill post pics for ID later). 1 yellow tang, 1 sailfin tang, 1 foxface, 1 flame angel, 1 Garibaldi (still a youngster), 1 saddleback clown, and the porcupine pufferfish. At exception of the 7 new fish, everything in my tank is around 6+ years old. (chromis, tangs, clown). I feed once a day. I know that a water change is in order, even though I dont look forward to moving around that volume of water. What do you guys say, 40G+ water change? I threw about 6 caps of Prime in there since the label says it detoxifies Nitrates. My chaeto is about as big as a basketball.. How small should I be trimming this thing for my size tank for better results? My refugium is a 55G tank but its maybe halfway filled. Skimmer was turned off for a while (mother doesnt know how to fix it when it starts overflowing and foaming so she shuts it off).