Urine Blood on fleece? PLEASE HELP

[Mintshare]

Hello everyone i have two female guinea pigs and i am really worried, tonight i was cleaning my guinea pigs cage and noticed two brown/reddish spots. They normally have white and yellow spots for their pee and i was told by my vet that yellow and white spots are normal, so what about brown/reddish stains? It does not seem like diarrhea as their poops look normal. My guinea pigs seems fine and are eating and drinking regularly. It must have happened today because i spot clean my guinea pigs cage every night and have only noticed it today. I have attached the two stains. If you guys have any information of what is happening please let me know. Thank you

 

[bpatters]

Guinea pig urine oxidizes when it dries, so it gets darker. And it gets darker for young pigs than for older ones. But that doesn't look like a urine stain.

Sows don't normally bleed during their heat cycles, but occasionally a sow will have a little spotting. If it clears up in a day or so, but then recurs in about 14-16 days, that's probably what it is. If so, it's nothing to worry about.

If you notice one squeaking while peeing or, particularly, pooping, you might be dealing with a bladder stone that's causing a bit of bleeding.

 

[Mintshare]

So a little update so far, after i found the stains i emailed my exotic vet and he told me to come see him if there is any other stains. I did not found any stains after that until i put them in their play pen with a dog pee pad and found out that one of them was peeing a brown-reddish tint urine. I brought her to the vet that next day and we did an x-ray on her and found no stones and the vet told me those stains are not blood. The vet told me to change up their vegetables to have a wider variety because that could be the reason why. Before i fed them kale, bell pepper and zucchini so now i switched to green lettuce, 1 cherry tomato, bell peppers, very little cilantro, zucchini and 1 baby carrot for both guinea pigs to share. I even tried to limit their pellet intake. I looked at her pee today and did not notice anymore red/brown tints in her urine. However one of the guinea pigs is having a calcium sludge deposit now, which has never happened before. In the past it was little calcium spotting but nothing severe. The calcium sludge is barely wet and turns into a soft powder like substance when broken. I haven't been able to pinpoint which guinea pig it is yet but i am thinking its the one with urine problem. They are both still doing fine, eating and drinking normally with no squeaking while peeing or pooping.
Is there anything else i can do to prevent this calcium sludge?

 

[FailedFoster]

It looks like it might be from the zucchini. Zucchini has a higher calcium content, so that could be the culprit. If you want a really handy veggie and fruit chart, GuineaLynx has a chart that's sortable by nutrient.

What brand/ kind of pellets are you using?

 

[Mintshare]

They barely eat the zucchini, maybe one or two small bites but eat every other given vegetables completely. I have to throw away the zucchini everyday because they don't finish it. I'm going to stop giving the zucchini anyways just in case. I give them oxbow young guinea pig pellets. They are about 6 months old and i am thinking of switching them to adult food soon. The calcium sludge is not happening everyday but i have found 2 calcium sludge in one week so i am concerned. It has only started happening once i switched their vegetable diet. But i think the vegetables i give them now has lower calcium than before as kale contains a lot of calcium so i am confused as to why they have the calcium sludge now. Also i forgot to mention the vet did not find any cyst either.