A20: Flourite starts out with nutrients (if I remember right) but is very dusty and needs to be rinsed EXTREMELY well or your aquarium will be cloudy for quite awhile. Laterite is not a substrate, but rather a way of adding nutrients to a substrate like gravel. From what I hear it's rather messy and can cause issues if accidently exposed to the water column. Eco-Complete has nutrients to start but after a year or so would need to be supplemented with root tabs. Turface holds nutrients really well, but does not have them to start.
The mulm created by fish waste etc does add nutrients to the substrate, but that doesn't mean that it will provide all the necessary nutrients. This is why you may find that root tabs are still necessary with heavy root feeders and/or when lightly fertilizing the water column.
A21: You're correct. It's more important to have a substrate that has a high CEC (ability to store and release nutrients) and doesn't negatively impact your water parameters than it is to have one that starts out nutrient rich. Having a nutrient rich substrate to start can be helpful in giving the plants a jump start, but you can achieve the same affect in other ways (adding mulm, dusting of peat moss, prepped dirt, etc).
A22: I've used the Flourish root tabs, and they worked fine. If I were to get more, I'd make my own.
A23: I'd probably put the inline reactor in the line going from the sump back to the aquarium. This way the CO2 goes through the aquarium once before getting gassed off in the sump. If you're willing to put up with the extra expense of more frequent fills, then you can certainly keep the sump. I'd recommend doing some research for ways to minimize the gas off as a result of using a sump. If I remember right there are some simple ways to mod the setup that will help quite a bit.
The mulm created by fish waste etc does add nutrients to the substrate, but that doesn't mean that it will provide all the necessary nutrients. This is why you may find that root tabs are still necessary with heavy root feeders and/or when lightly fertilizing the water column.
A21: You're correct. It's more important to have a substrate that has a high CEC (ability to store and release nutrients) and doesn't negatively impact your water parameters than it is to have one that starts out nutrient rich. Having a nutrient rich substrate to start can be helpful in giving the plants a jump start, but you can achieve the same affect in other ways (adding mulm, dusting of peat moss, prepped dirt, etc).
A22: I've used the Flourish root tabs, and they worked fine. If I were to get more, I'd make my own.
A23: I'd probably put the inline reactor in the line going from the sump back to the aquarium. This way the CO2 goes through the aquarium once before getting gassed off in the sump. If you're willing to put up with the extra expense of more frequent fills, then you can certainly keep the sump. I'd recommend doing some research for ways to minimize the gas off as a result of using a sump. If I remember right there are some simple ways to mod the setup that will help quite a bit.