Before the bag comes home: check the destination tank
Angelfish settle best when the tank they enter is already stable, so test ammonia, nitrite, nitrate, pH, and temperature on the day of purchase and correct anything off before the fish arrive. Angelfish prefer warm, steady water and vertical space, so confirm the heater holds its setting and that tall plants, driftwood, or other upright structure give newcomers somewhere to retreat behind. Check compatibility honestly: adult angelfish can prey on very small fish, and fin-nipping tankmates will target their long fins, so a calm community of similarly sized fish is the right receiving group. Decide in advance whether a separate quarantine period is practical for your setup. Also plan where a divider or spare tank would go if one newcomer is singled out.
Equalising temperature, then chemistry, in stages
Float the sealed transport bag in the tank for about twenty minutes so temperatures meet gradually, keeping room lights and tank lights low to reduce stress. Then open the bag, roll the top down to keep it floating, and add a small cup of tank water every five to ten minutes. Continue for at least thirty to forty-five minutes, longer if the shop's water is known to differ greatly in pH or hardness, removing some bag water if it fills. This staged mixing protects angelfish from the abrupt chemistry swing that a simple float-and-release causes, which is a common trigger for clamped fins and refusal to feed after arrival.
Releasing angelfish without importing bag water
When the bag water closely matches the tank, net each angelfish gently and lower it into the tank, letting it swim out on its own rather than tipping it. Discard the bag water down a drain, never into the aquarium, because it can carry waste built up in transit and anything present in the shop's system. Leave the lights off for the rest of the day, resist feeding for several hours, and watch from a distance: some initial hiding and a mild squabble as the existing hierarchy adjusts are normal, but persistent chasing or fin damage means a bully needs separating.
The first week with new angelfish
Feed small amounts once the fish begin exploring, usually by the next day, and confirm each newcomer actually eats rather than assuming the group feed reached it. Test the water every other day during the first week, because the added fish increase the load on the filter, and do a partial change promptly if ammonia or nitrite appears. Keep hands, nets, and redecorating out of the tank so territories can form undisturbed. Note appetite, fin condition, and interactions daily; a healthy angelfish should hold its fins erect, cruise the middle levels calmly, and show brightening colour within days.
Sharing the settling plan with everyone at home
New fish fail most often when several people feed, test, and tinker independently, doubling meals and undoing each other's water changes. Agree one feeding amount, one testing schedule, and one person logging results for this introduction. Using KinsLe's Family Sharing to share the angelfish's profile and care notes means every helper in the house follows the same acclimation record and first-week plan.