Cheapest way to maintain a prepaid second phone number

BSNL 365

Use jiodhandanadhan

Jio no plan required for active incoming or for incoming messages but for outgoing min plan is of ₹129.

Check this https://www.doosr...m/

Choose any operator
Recharge for 48/49 per month

LOL
Get a MTNL Dolphin sim and pray that the merger never happens

BSNL is better choice if you have good network in your area.
50 rs topup is sufficient to keep sim active for 60 days as they deduct 2 rs for every 3 days.

I am planning to get Jio so when we take new prepaid sim, what is the minimum FRC (first recharge) they will tell me to do? Also after that, can I just do a topup on my number and keep that balance so that incoming text and calls will remain on?
Will it work that way?

I am presently using Vi as secondary no. Do recharge of 95 every 56 days. If recharge is done on 55th day, unused secondary talktime and data balance gets carried forward.
Also got a MTNL Delhi no that gives for extension of validity by 90 days with 47 recharge (use it only as a backup in remote locations on BSNL network where all other networks fail)