I have not seen anyone try DCA with altcoins, and I do not know whether it was a successful strategy or not.
1000 dollars is a good amount for a beginner. If you could do DCA with Bitcoin, it would be better. Stellar has not reacted well in the past years, so what is the reason for you to invest in it?
I use the DCa method for alts. But to effect this, you need to have basic TA knowledge so you'll know the support zones etc.