How much water do I truly need to drink? Should i Up my protein??

Well, I've been doing great so far 61 pounds down and almost 4 months post op. I work out 5 days a week ( 3x with a trainer and 2 cycling classes/trail run). I'm also training for a tough mudder coming up this fall. I eat between 650-750 calories, protein 80-100 grams carbs 40 or under and I try to aim for 96 ounces of water. I'm thinking my water intake should be 128 ounces (a gallon a day)? My weight loss for month 4 is taking its good old time! So far 8 pounds down and one more week for 4 month mark. I'm so use to a solid double digit loss that its driving me crazy lol Should i up my protein since I'm working out so much?

I think your stats are pretty awesome!  I only lost 7 in month 4.  Went on to have my first stall in month 5-6.  Your cals/protein/carbs/liquid all look good!  Stick to it, you've got this.  xoxo

I don't know - upping your liquid if you're sweating a lot would be wise.  But I exercise between 1-3 hours a day and haven't upped my protein or calories to compensate.  I do add BCAAs to my shake to help with muscle recovery.  These would be good questions to ask your nutritionist or trainer.  Or both!  

8 pounds in 3 weeks sounds awesome to me :)  

What are BCAA's?

Branched Chain Amino Acids.

Here's the specific brand I use - http://www.amazon.com/Optimum-Nutrition-Instantized-Powder-O range/dp/B00CBS9L8G/

It always starts to slow down after around 4-6 months , there is less of you to burn calories

 do not increase cal because you are exercising you want to use more than you eat

unless you are seeing sighs of dehydration you are drinking plenty , 65 oz is what is recommend

I don't know how you are getting 80-100 grams of protien with only 650-750 cal

 10 cal per gm protien is normal  and that would add up to 800- 1000 cal

I still use 1 or 2 protein shakes depending on how hungry I am and that is 30 grams of protein in one shake. I use premier protein. I also eat every 3-4 hours so 5-6 small meals of dense lean protein anywhere from 3-4  ounces. It is possible to get 80-100 grams of protein with only 650-750 calories. The only thing i am experiencing is fatigue maybe from the calorie loss? I do a monthly B12 shot.

64 oz is the daily minimum.  If you're working out hard, drinking more is a super idea. 

Your loss will naturally decline as you proceed thru this as you simply have less weight to push around as you lose (as a reference, my monthly loss was 32, 15, 15. 10, 10, 10.) Looking at others' loss progression, you will find a similar pattern, though some may not have as smooth a time, experiencing a month of relatively low loss followed by a month of higher loss. It looks like you are doing the right things to keep everything moving in the right direction!

You may well need more water with the amount of work that you are doing. One thing to try if it is not too inconvenient is to weigh yourself naked before and after your workouts to see if you are drinking enough during the workout to replace your sweat loss (each pound down during the workout is 16oz of extra water that you need to replace, give or take a bit for scale repeatability.)

Your protein intake is probably fine for your size - it's enough to maintain your lean mass (which is what we are after in our loss phase) though you may need more if you wish to actually build muscle mass later when you get to maintenance (it's real tough, if not impossible, to build lean mass while in the caloric deficit mode needed to lose fat and total weight.)

You might find that you need to increase your complex carbs some ahead of some workouts if you experience any endurance problems (which can come from either an increase in the total or a reallocation or re-timing of the ones that you are already consuming.) I needed a boost to take my swimming beyond an hour and did it by reallocating my non-protein calories.