You should consider getting a better source for MDMA. There's no way you would even want to go through a whole gram of real, high purity MDMA or MDA. I used to go through half grams in a night until I discovered what the pure pure is like. The best MDMA I've ever had, none of my friends wanted more than 80 -100mg, even the hardheads.
The synergy is insane with LSD; if you are taking 300 ugs of real LSD (which is likely a BS number, 99% of people who eat "acid" dont have the means to be sure of how many ugs are on each hit), I don't recommend anything more than 75mg of MDMA. You'll be good, unless your drugs are just shitty.
Also DMT after LSD vs DMT after MDMA is very different experiences. Both great! So is DMT after L+MDMA. It's just important to be responsible with your doses if you want to actually enjoy yourself.