One cloudy eye-then 3 yrs later the other eye goes cloudy

[FBTmom]

Hello,
When we rescued our two FBT's from my son's gr. 4 classroom 3yrs ago, one of the toads had a cloudy eye. Considering the bad living conditions these two were in (a plastic betta container for 2yrs plus kids poking at them) I figured it was an injury.
Now, 3yrs later, the other eye has gone cloudy! Plus the 2nd toad has one cloudy eye now. A 3rd toad we purchsed about 2yrs ago has clear eyes. All three are in the same tank.
From what I've read, it sounds like it could be some sort of fungal infection, but maybe not. I do regular water changes, and I use dechlorinator each time. They live in a 35 gal. tank that's 60% (heated) water, 40% land. The toads are fed every 3-5 days, having two to three crickets each. The one with two cloudy eyes has trouble with his aim (my son hand feeds them all), but my son touches his mouth with the cricket, then moves it half an inch away so he can get it. He still has a good appetite. This toad also spins a lot in the water, and he's not as actively moving about the tank as he used to be. It's like he can't see properly, if at all so, he just stays put most of the time in the water. He used to watch us move all over the house like the other two do, following our movements, but not anymore. Sometimes he'll sense us near, or we'll have our hand in the tank to adjust a rock or something, and he'll jump up, like he's thinking were're holding food out for him and he's trying to grab it.
The 2nd toad with one cloudy eye hasn't changed his behavoiur, but his other eye is still clear so I'm not sure if he has limited sight in the cloudy eye or not. If I move my finger on either side of his head, he ignores me or takes off.

I live in a small town with a vet that knows nothing about anything except cats and dogs. Our pet store has no idea, nor do they have anything except basic fish meds. I wouldn't know what to use anyway, or what to do, since I have no idea what could be wrong.

Could putting too much dechlorinator in the water harm them? I use AquaPlus. I also keep a bucket full of water, without declorinator, near their tank so I can top up the water in between changes, if needed, but it always sits at least 24 hrs before I'll use it so the chlorine will be gone.
I just don't know what to do or even where to start. I'm so worried the second frog is going to get the cloudiness in his second eye. Or frog #3 will get it.

If anyone has a suggestion, I would be so grateful. I'm so worried about these guys, and I feel so awful thinking they may be losing their sight. It's so frustrating living in a small town sometimes! If there's any way to clear this up and fix it............

Thanks so much,
Diane