Discus are extremely sensitive to pH differences. During acclimation, it is suggested to adjust pH values accordingly and take twice the regular time to introduce new specimens.

These cichlids are often very territorial. Rearranging the rock structure can reduce aggression towards newly introduced specimens. Certain species of Lake Tanganyika cichlids (especially fry) are sensitive to changes in water chemistry. Slowly dripping water into the bag for 30 to 40 minutes is recommended.

Marine fish should be introduced with caution, slowly dripping water into the bag for 30 to 40 minutes until the bag volume has doubled. Marine tanks with larger, territorial species such as surgeons and angels may require the use of a see-through divider (that does not impede water flow) to prevent serious attacks on new specimens.