Maybe you're just not understanding, i do 30-50% changes every week with prime, gravel vac, i have a 55 gallon, 25 fish and my nitrate was through the roof.. Let me put this in different words, No matter weather you do a water change a week you do not know the parameters.. you only think your levels are good cause you use a conditioner, they aren't, from the pic i don't know if that's a separate tank but it has no substrate, what filter do you have , is the filter a cartridge style , does it have media, reason why i ask, with no substrate that's 20% of your beneficial bacteria, your filter is 80% if you have no media in your filter Where's the beneficial bacteria... You have asked for help on a forum, people have told you what you need but you assume everything's perfect cause you do water changes. At least tell people your setup
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