My plants look like they are melting

Plants dying back or melting is a common occurrence and can be caused by a few factors.

1. The plants are new to being submerged in water. Most aquatic plants farms grow their plants above water and only get submerged in water at the aquarium store. This causes the plants to become stressed and go through a conversion to underwater growth, often looking like the plants have been boiled in water and melting. Remove the dead leaves and monitor the plants for new growth which will come for the centre or stem of the plants as long as the starts of new growth can be seen there is nothing to worry about.
2. The second reason a plant in particular stem plants will melt and float out of the substrate is usually caused from the elastic band wrapped around the base bruising or cutting the stem. Make sure you remove the elastic bands and cut off any bruised or rotting stems before planting this will allow the plants to focus on producing new roots and not trying to save dying stems.
3. Plants that have been moved from one tank to another can become shocked by moving in a different environment especially if they have a well developed root system. The will die back and regrow this is very common for crypts and sword plants, if the have huge root systems that make it difficult to replant them don’t be afraid to trim some of the roots before replanting.
4. The last reason plants melt is because of nutrient deficiencies, make sure that you use an aquarium safe comprehensive fertiliser. This will help prevent these deficiencies but remember the more plants you have the more often you will need to fertilise.