What type of substrates are good for planted tanks..I’m trying to avoid regular gravel or sand since you have to dose with fertilizers or use root tabs - thanks!
If you want to avoid all of those (and the hassle with a soil based substrate capped with sand), you can always try some of the following;
Carib Sea Eco Complete
They normally use pre-loaded volcanic clay that holds onto fertilizers and releases them over time. Normally if you use those, throw in root tabs before laying down, and then dose fertilizers like once a month it will pretty much stay charged for a very long time (others the charge normally lasts for a few months to a year before being depleted and needing to be recharged via dosing).