We have been having a hard time finding plants that will thrive in this tall tank. We are using a Finnex planted 24/7 light. We use plant food. Could substrate be an issue? It's a mix we found at a co-op fish store called Super Sand. "This is a coarse sand that is optimal for growing plants and allowing root hair growth. It is much heavier than other sands but not as large as gravel. It is Cenex brand sand if you can find it locally at a gravel yard. It has been washed and kiln dried and is ready to go into a tank with very little dust." We received these beautiful red plants and it's been terrible watching them "melt" away. If using Co2 and other complicated methods are needed to grow red plants then that's not for us. With our busy lives, 3 kids, 2 cats, 1 dog, 3 birds and 4 tanks (60g, 2 20g long, 10g) we have plenty of upkeep chores to do. Not to mention our garden! Any who, I'm hoping some of you could give us some insight as to what we could change, add or try! Thank you!