Hi all. My name is Alex. I am brand new to this site and pretty new to the aquarium world. I have a 55
gal freshwater tank that has been up and running for about 6 months since i upgraded from a 20
gal. I am running a Marineland emporer 400
HOB and a Fluval 306 for filtration. I have a 10-12 inch tiger oscar (bubba), an 8 inch red devil, an 8 inch polystigma, a 4 inch yellow lab, a 4 inch african leaf fish, a 5 inch raphael catfish and a 12 inch pleco. Until earlier today i also had a frontosa but when i did a water change and left to but new filter media I came home and it had died

my nitrates have been off the charts for months now and i have started doing regular 50% water changes but it doesnt seem to help much. My pH is also chronically low and I have recently added crushed coral to help. Guy at my local fish store told me to 86 the canister and get another
HOB to help with nitrates. Any help/opinions?
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