How exciting about Manny.

The see through spots on c-thru may be indications of fin rot. Remember that the care they receive at the pet stores may not be ideal as well as the stress from being shipped. Keep an eye on those spots. Pics now may be helpful for comparison.

As for the nitrite spike, that is normal for the cylcing process. Nitrites as not as dangerous as ammonia, but it isn't good to have high nitrites either. The only thing you should do is change a little bit of the water every week (maybe a few cups since it's a gallon bowl). You may also want to try adding some cycle (a beneficial bacteria additive).

Do you know about the cycling process? Have I sent you the cyling article before?
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Phishie
Site Coordinator

"An ounce of prevention is worth a pound of cure."