Looking for a little help

[The Morning]

So I purchased this pleco about 7 months ago as an albino bristlenose at the same time that I purchased another from the same tank at the LFS. Over the past few months the two fish have developed differently. This fish has zero “bristles” and is much stockier than the other.
I just want to know what I have here. Plecos are by no mean my area of expertise.

 

[Niki_up]

First question is this the same fish in all pics? I only ask bc this gosh looks more brown/purple. The second last photo looks closer to albino color. If I had to guess that picture might be one the first pictures you took of it? If so it had darken considerably since you bought it? If the answer is yes then I would highly suggest you test your water for ammonia, nitrites, and nitrates. The brown/purple color is concerning to me and indicative of a water problem. Maybe a cycle problem?

Regardless, to answer your question this is a female bristlenose. Females have less or no bristles compared to the males.
The size you are noting is a sign she has produced eggs and is probably ready to lay eggs soon. If she fattened up since you brought her home it could be that you are feeding more and better foods, allowing her to gain extra energy for egg preparation.

 

[The Morning]

Thank you very much for the response. All of these are indeed the same fish and were also all taken within a few minutes of each other last night.
Tested water produced no notable issues. Both nitrite and ammonia came back at zero and nitrates roughly 10 but I will continue to monitor.
I may move the female to my planted tank that has the other albino which I now assume to be a male since it has bristles.

 

[Niki_up]

Well as long as your water is good she should be fine. The color still worries me, I would just keep an eye on her for worsening or improvements.

as long as the bristles go up the middle of the face and are plentiful then yes most likely a male. If it is just a couple of bristles it might be female.