Thought this guppy was male...

[Blackin]

But he... she.... it... keeps getting fatter and fatter. But there's no gravid spot. Is it due to the fact this fella is orange and white and no "clear" area for the spot to show?
And, last couple days, it's been pretty much laying on the bottom instead of running amuck around the 40g breeder with everyone else.

It looks to me like he has more "boy parts" than "girl parts", but I can never seem to get a really clear shot to show you guys.

 

[SpaceFish42]

It looks like a male, and I don't think pregnant guppies would not have that much trouble swimming.

 

[coralbandit]

Yes looks like male parts(gonopodium)?
How long have you had gup?
Could be a internal parasite/worm.

 

[Blackin]

How long have you had gup?
Could be a internal parasite/worm.

Have had that particular one just a couple weeks. Reckon I should pull him out and isolate him in another tank? Maybe something that could spread?

 

[TMRC Exotics]

Does look male, a shot of the gonopodium would tell for certain. Is this pic right after feeding?

 

[coralbandit]

Have had that particular one just a couple weeks. Reckon I should pull him out and isolate him in another tank? Maybe something that could spread?

Read up on praziquantel.
Very safe wormer that can be used in the main tank to avoid added stress to infected fish AND treat all that may have been exposed??
Praziquantel is a brand already mixed with liquid.
Could also be constipation?
Many offer shelled peas to their fish and Epsom salts can be used if you read up on them with out much danger to tank.
Many also skip one day a week feeding?
All other fish are well?
Neons look good.
Good luck!