The big clean up

I'd let it go too long.  The water was significantly lower than it should be and the algae had coated the inside of the tank.  Problem was it was a big job and I just couldn't bring myself to find the time to do it.
Finally, when I was overwhelmed by guilt, I did.  I took the goldfish out of the tank and set to work.
I used the gravel vacuum.  I scrubbed the glass.  I washed the tank ornaments and even replaced the plants.  I also took care not to completely change the water.  I tried to leave enough to keep the tank in balance, but as I took the water out, the crap in the gravel got stirred up and there was much more of it than I'd expected.  I guess that's what happens when you have goldfish, the poopingest fish in the universe, and little boys who sometimes overfeed them when you aren't looking.  And when you put off cleaning the tank far too long.  Far. Too. Long.
After the clean up, I let the filter work for a bit and made sure the water cleared before I put Goldy and Spotty back in the tank.  And they seemed happy for a bit.  For about two days really.  Then they didn't seem so happy.  Unfortunately I'd caused too much disturbance in their tank and even after I removed them to a "hospital tank" they were unable to recover.  Both of them died.
I hid the bodies since they died at night, had to decide what to tell the boys.  If anything.  I considered the great stealth fish swap, but honestly, the idea of it was too much for me.  The tears and emotion involved in losing a pet, even as minor as a goldfish, are hard for me to take and Little Dog seemed to be very attached to his Spotty.  And I thought maybe it was time to move to a more sustainable type of fish.  Something that isn't off the charts in poop production.  Something that doesn't need a bigger tank in the near future.  I spent the next day trying to decide what to do, and feeling pretty guilty about killing the fish, even if I was trying to do a good thing. 
I did a little research and decided that the best thing to do was tell the truth.  Then we'd replace the fish with something else.  Guppies and aquatic frogs.  Smaller. Cleaner.  Easier to care for.  I also decided I'd upgrade some of the tank equipment to make the maintenance a bit easier since in my research I discovered that I'd probably been getting less out of my filter than I'd expected.
I set up the tank and made sure the water was properly established.  We got the tiny aquatic frogs and the guppies- which are surprisingly beautiful and active.  So far so good.  Though I am obsessively checking the water quality, which is probably good for them but is definitely turning into a compulsive behavior for me.  And if they weren't so hard to photograph, I'd post a photo.  But they are, so I'm going to leave this up to your imagination.

Update:  Manged to snap a picture of at least one of the guppies and another of one of the frogs. 
 

Giuseppi the guppy

Dwarf frog- hard to know which one.