hello everyone. just did a 100% water change + cleaned the sand quite deeply after neglecting this tank for a bit. it’s 7 months old and the rock i purchased was live from a hobbyist, safe to say it was seeded for 1yr+ for sure. i plan on adding a lionfish in here but was wondering how long it’d take to know if i have to re-cycle the tank tested in 24hrs but theres no source of ammonia or nitrites atm and i prefer not to dump pure ammonia to double check since i still have my urchin in there so i’ve dosed bacteria and prime for now just in case.. what do you think? is it safe to add a lionfish considering the live rock + biomedia + liverock rubble in the sump.. would removing 100% of the water and messing with the sand be enough to restart the cycle? thanks for any input to whoever bothered to read this lol
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