I recently set up a 75 gal tank and started a fishless cycle. Everything was going fine, ammonia was dropping to zero everyday and i would bring it back up to about 4ppm, nitrites had spiked and i was even showing nitrates. About 4 weeks in i started getting some red/brown algae that i figured formed from the high ammonia/nitrates. A week later i started getting a bright green algae on everything but ammonia was still dropping everyday and nitrites were still high now all of a sudden the ammonia has stopped dropping and stays high, the nitrite test starts out purple and then goes to a blue/green color thats not on the chart the water also has a musty smell to it. I didn't anything to it during this time except add the ammonia (Ace Hardware brand). Can anyone tell me what happend and what i need to do, like drain the water and start over or what. Any input would be greatly appreciated im tired of looking at an empty tank! its been about 7 weeks now.
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