Wanting to stream a symple int EarthLifePoints to all players so earths life is the same for all players.
using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class Earthlife : Photon.MonoBehaviour {


	public static int EarthlifePoints = 100;
	public Text EarthlifeTxt;
	// Use this for initialization
	void Start () {

	}
	
	// Update is called once per frame
	void Update () {
		if (photonView.isMine) {
			//displayEarthlife
			EarthlifePoints.Text = "%" + Earthlife;
		}
	}

	public void OnPhotonSerializeView(PhotonStream stream, PhotonMessageInfo info) {
		if(stream.isWriting) {
			//stream Earth Life to all players.
			stream.SendNext(EarthlifePoints);
			stream.SendNext(EarthlifePoints);
		}
		else {
			//stream Earth Life to all players.
			(EarthlifePoints)stream.ReceiveNext();
			(EarthlifePoints)stream.ReceiveNext();
		}

	}
}

Change

             //stream Earth Life to all players.
             (EarthlifePoints)stream.ReceiveNext();
             (EarthlifePoints)stream.ReceiveNext();

to

             //stream Earth Life to all players.
             EarthlifePoints = (int)stream.ReceiveNext();
             EarthlifePoints = (int)stream.ReceiveNext();

Edit: Although after further consideration I can’t understand why you are sending and receiving the same data twice each time. I think you might want to change your function to

     public void OnPhotonSerializeView(PhotonStream stream, PhotonMessageInfo info) {
         if(stream.isWriting) {
             //stream Earth Life to all players.
             stream.SendNext(EarthlifePoints);
         }
         else {
             //stream Earth Life to all players.
             EarthlifePoints = (int)stream.ReceiveNext();
         }
 
     }