I'm glad you got the T5 UVB tube finally mounted within the correct distance, 12" is perfect. The reason i was concerned about him having vision issues is if I recall you had the coil UVB over him and it was very close, then I believe you had another light very close, and that is usually what can cause at least temporary vision issues. But if the reptile vet checked that out then that's good news.
As Tracie already mentioned, the liquid calcium is a must when you're first dealing with MBD, as it's absorbed by the body much more readily. As far as the multivitamin goes, you may want to check out Repashy Calcium Plus, I love this multivitamin supplement and have been using it forever, the reason being is that it contains no synthetic vitamins or minerals at all, they are all sourced from natural sources and this not only prevents any vitamin toxicity as often happens with synthetic vitamin supplements, but the vitamins and minerals from all-natural sources are also much more readily absorbed by their bodies.
I'd completely agree with you that Bearded Dragons are certainly not the "Beginner's Reptiles" that they are often labeled as being. I happened to look at my local Petco the other day at the babies they had, killing time while I was waiting for someone to count out some crickets for a friend of mine, and I noticed on the little "information cards" they have under each tank, which describe the average life-span, whether or not they need "specialty lighting", etc. that the information card underneath the baby Bearded Dragons said that their "Level of Care" was labeled as "Easy, Beginner"...Then I looked at other cards under different lizards, snakes, and a Herman's Tortoise, and they have levels that also say "Moderate", "Expert", and "Advanced Care", so according to Petco Bearded Dragons don't even require "Moderate" care or experience. I suppose that's true if you care for them like Petco now does; since they made Zilla their new "House-Brand" last year they have been keeping them on bright white Calcium Sand (little tiny babies no longer than 3-4" on over an inch of Calcium Sand), and they now have an 18" Zilla Desert 50 T8 UVB tube mounted about 4" above the mesh lid to the tank, up in a rack system, and the tube is in that damn Zilla Slimline Fixture with the clear, plastic cover over the tube that is blocking 100% of the UVB light emitted. Not that it would matter if the clear, plastic cover was on the fixture or not, they've got the tube mounted 4" above the mesh lid, so there's no way an unobstructed T8 Zilla tube would deliver any UVB light at all to the poor dragons inside a regular 20 gallon tank that has to be 18" high, then through a mesh lid, then 4" above that...I said something to the aquarium guy that I know there who actually really knows his aquariums, he has literally forgotten more about fish aquariums than I've ever known. So I thought the UVB light issue would make sense to him, which it did, and he was already fully aware of the issue, but said he can't change it, no one in the store can change it now, not even the managers, because of the deal they have with Zilla now. What a bunch of crap.
Anyway, the point I was making is that Bearded Dragons are universally excepted as "The perfect beginner reptile pet for kids and people who have never owned a reptile before", and I have no idea why. In my opinion NO desert reptile is going to be a good "beginner" reptile, or a good first reptile for a young child to take care of, simply due to their very specific and lighting requirements. Why not suggest a Leopard Gecko as a first reptile for a child? They are extremely easy and straight-forward to take care of, they can eat pretty much any live feeder insects, they only require minimal UVB/UVA lighting, and their temperature requirements are no big deal. Very, very simple. I think the reason that Beardies are represented as a great "beginner" or "child's" reptile is because they are very docile, interactive, and friendly, even loving. That's why. Most Geckos don't like to be handled, neither do Anoles (another extremely easy lizard for a child to care for), and the monitors and such are too big. I guess that's why. The problem is that if their husbandry isn't completely correct then they aren't going to be friendly or interactive anyway because they're sick, and the owners spend all of their time and money trying to get them well again. It's very unfair of pet shops to represent Dragons the way that they do, unfair to both the Dragons and to the poor people who buy them.
The good news is that your little guy is young enough that he'll be able to recover, it's just going to take a while. Once you get over this hump it does in-fact get much, much easier, the only thing you need to remember is to replace the T5 UVB every 12 months, that's about it as far as any husbandry changes. So please try to keep that in mind, that there is light at the end of the tunnel, and once you get her through this initial set-back she's going to be a very loving, fun pet that will become extremely easy to care for.
I wish that pet shops and breeders, when dealing with customers who are buying their first Dragon, would suggest to them that they might want to buy or adopt an older juvenile or a very young adult dragon that is already through the first few "baby" months of life. As long as the juvenile or sub-adult/adult that you're getting has been well taken care of and has grown to full potential, and is eating well, it's much easier to start out that way sometimes...
As Tracie already mentioned, the liquid calcium is a must when you're first dealing with MBD, as it's absorbed by the body much more readily. As far as the multivitamin goes, you may want to check out Repashy Calcium Plus, I love this multivitamin supplement and have been using it forever, the reason being is that it contains no synthetic vitamins or minerals at all, they are all sourced from natural sources and this not only prevents any vitamin toxicity as often happens with synthetic vitamin supplements, but the vitamins and minerals from all-natural sources are also much more readily absorbed by their bodies.
I'd completely agree with you that Bearded Dragons are certainly not the "Beginner's Reptiles" that they are often labeled as being. I happened to look at my local Petco the other day at the babies they had, killing time while I was waiting for someone to count out some crickets for a friend of mine, and I noticed on the little "information cards" they have under each tank, which describe the average life-span, whether or not they need "specialty lighting", etc. that the information card underneath the baby Bearded Dragons said that their "Level of Care" was labeled as "Easy, Beginner"...Then I looked at other cards under different lizards, snakes, and a Herman's Tortoise, and they have levels that also say "Moderate", "Expert", and "Advanced Care", so according to Petco Bearded Dragons don't even require "Moderate" care or experience. I suppose that's true if you care for them like Petco now does; since they made Zilla their new "House-Brand" last year they have been keeping them on bright white Calcium Sand (little tiny babies no longer than 3-4" on over an inch of Calcium Sand), and they now have an 18" Zilla Desert 50 T8 UVB tube mounted about 4" above the mesh lid to the tank, up in a rack system, and the tube is in that damn Zilla Slimline Fixture with the clear, plastic cover over the tube that is blocking 100% of the UVB light emitted. Not that it would matter if the clear, plastic cover was on the fixture or not, they've got the tube mounted 4" above the mesh lid, so there's no way an unobstructed T8 Zilla tube would deliver any UVB light at all to the poor dragons inside a regular 20 gallon tank that has to be 18" high, then through a mesh lid, then 4" above that...I said something to the aquarium guy that I know there who actually really knows his aquariums, he has literally forgotten more about fish aquariums than I've ever known. So I thought the UVB light issue would make sense to him, which it did, and he was already fully aware of the issue, but said he can't change it, no one in the store can change it now, not even the managers, because of the deal they have with Zilla now. What a bunch of crap.
Anyway, the point I was making is that Bearded Dragons are universally excepted as "The perfect beginner reptile pet for kids and people who have never owned a reptile before", and I have no idea why. In my opinion NO desert reptile is going to be a good "beginner" reptile, or a good first reptile for a young child to take care of, simply due to their very specific and lighting requirements. Why not suggest a Leopard Gecko as a first reptile for a child? They are extremely easy and straight-forward to take care of, they can eat pretty much any live feeder insects, they only require minimal UVB/UVA lighting, and their temperature requirements are no big deal. Very, very simple. I think the reason that Beardies are represented as a great "beginner" or "child's" reptile is because they are very docile, interactive, and friendly, even loving. That's why. Most Geckos don't like to be handled, neither do Anoles (another extremely easy lizard for a child to care for), and the monitors and such are too big. I guess that's why. The problem is that if their husbandry isn't completely correct then they aren't going to be friendly or interactive anyway because they're sick, and the owners spend all of their time and money trying to get them well again. It's very unfair of pet shops to represent Dragons the way that they do, unfair to both the Dragons and to the poor people who buy them.
The good news is that your little guy is young enough that he'll be able to recover, it's just going to take a while. Once you get over this hump it does in-fact get much, much easier, the only thing you need to remember is to replace the T5 UVB every 12 months, that's about it as far as any husbandry changes. So please try to keep that in mind, that there is light at the end of the tunnel, and once you get her through this initial set-back she's going to be a very loving, fun pet that will become extremely easy to care for.
I wish that pet shops and breeders, when dealing with customers who are buying their first Dragon, would suggest to them that they might want to buy or adopt an older juvenile or a very young adult dragon that is already through the first few "baby" months of life. As long as the juvenile or sub-adult/adult that you're getting has been well taken care of and has grown to full potential, and is eating well, it's much easier to start out that way sometimes...