To better assess the situation, could you please share a photo of your entire tank setup, including the plants?
Echinodorus species, commonly known as swords, grow from the center of the crown, producing new leaves while older outer ones may die off over time. The rate at which this happens largely depends on your tank's conditions, specifically the lighting and nutrient levels. Once I get a glimpse of your setup, I might be able to offer more specific advice.
As heavy feeders, these plants require a good amount of nutrients to thrive. Are you currently using any fertilizers, either liquid or tablet form, and if so, which ones?
Is amazon swordplant melting a common issue?
Re: Is amazon swordplant melting a common issue?
First on nutrients. I'd advise against using the CO2 Booster as it's a derivative of glutaraldehyde, a toxic disinfectant that can harm fish over time. Consider switching to Seachem Flourish Tabs instead of the API tabs, as they provide a more comprehensive range of nutrients. If you're using API's Leaf Zone, keep in mind that it only contains potassium and iron, so you're missing out on other essential micronutrients. I'd recommend Seachem's Flourish Comprehensive Supplement or Brightwell Aquatics' FlorinMulti for better results. I'm confident you'll see an improvement in your plants.
Regarding the lighting, it's crucial to have a single, continuous "daylight" period. This is more important for the fish than the plants. I've written an article on this topic, which explains the reasoning behind this. As for algae, reducing the photoperiod and using the right fertilizers can help control it. My tanks run for 7 hours daily, and I've been algae-free for six years. This is all covered in the article. I'd also suggest adding some floating plants, as they can prevent algae and provide shade for your fish. In my experience, fish don't appreciate direct overhead light, and floating plants can help with this.
Regarding the lighting, it's crucial to have a single, continuous "daylight" period. This is more important for the fish than the plants. I've written an article on this topic, which explains the reasoning behind this. As for algae, reducing the photoperiod and using the right fertilizers can help control it. My tanks run for 7 hours daily, and I've been algae-free for six years. This is all covered in the article. I'd also suggest adding some floating plants, as they can prevent algae and provide shade for your fish. In my experience, fish don't appreciate direct overhead light, and floating plants can help with this.