Hi!
Ureter stones can be even trickier to get out...
Please follow our diet advice with filtered water and limited low calcium/grain-free pellets (max. 1 tablespoon per piggy day, preferably even less). Most people are not aware that most of the calcium in the diet comes with these two food groups. Even the no added calcium pellets contain more calcium than the richest calcium veg. We recommend to combine some trace element rich herbs and veg with mostly watery veg or fresh grass to encourage good urination. Hay remains the staple and main food source; what most people don't know is that fresh grass is rich in vitamin C and that hay also contains it - it is the reason why guinea pigs have never had the need to make their own in the first place. Please be cautious when introducing fresh grass into the diet as it can cause tummy upsets.
You can find the full details in the special diets chapter in our comprehensive diet guide. All I can say that I live in one of the more tricky parts in the country but I haven't had any new bladder stones for the last 8 years since I started filtering water and made the other diet changes.
Here is the link (you may want to bookmark it):
Long Term Balanced General And Special Needs Guinea Pig Diets
All the necessary tips for grass feeding and lawn time:
Feeding Grass And Preparing Your Piggies For Lawn Time
Feliway cystease capsules for cats (UK brand name) are the easiest to way to give measured glucosamine without having to grind down tablets and work out the dosage. You mix the contents of 1 capsule with 2 ml of water and give 1 ml of the shaken and dissolved mix every 12 hours. Always shake before use. A little medicine bottle is ideal for mixing.
Please be aware that glucosamine is no bladder stone deterrent. It is there to support the natural glucosamine coating in the walls of the urinary tract. It is this glucosamine coat that prevents the corrosive urine coming into very painful contact with raw tissue. Ultimately it is about comfort and healing the walls of the urinary tract.
This is not a medication but classed as a food supplement. The Oxbow nibbles are also glucosamine based.
Please accept that both diet and glucosamine will take several weeks to build up and work through the body. Calcium absorption is a complex process where lots can go wrong and does play into. What we recommend are long term measures and not a quick fix; but they are the most effective measures you can take.
If the calcium absorption process is for some reason going wrong, you can end up with more stones in a matter of weeks. There is unfortunately nothing that can stop this, medically or nutrionally. None of the 'miracle cures' that have been (or still are) making the rounds have sadly stood the test of time. You have to get through the next few months first and then you should hopefully be in the clear for the long term.
The good thing with bladder stone op that have not damaged the bladder or pipes too badly is that the sheer relief from pain generally leads to a very quick recovery of any lost weight, so don't worry - the rest will come back on in its own time.
I hope that this helps you?
So glad your lad’s doing ok, great weight gain for him, he must be feeling much better! 
He's a little sweetheart so am really relieved he's made it this far.
