Sounds like your tank somehow traveled back in time, meaning something changed your bio filtration that breaks the amm. down to the nitrite->nitrates you normally see in a cycled tank.
Did you change gravel to NEW or clean the tank with HOT water? this would kill the bacteria that should have been present. Also sometimes adding NEW (mostly a lot) of "bodies" to the tank could throw it off.
Anyways, the blackworms are alive right? If so, the worms will travel into the gravel and HIDE; will live down there and could cause an amm. increase (if there's TONS of them in there.) Live worms should be fed on a plate (glass, plexi) to assist in the "gravel" problem, but not 100% successful.
My easterns, CFB's, etc.. love frozen (thawed of course) brine, and bloodworms, and will eat them without problem or "something living in the gravel later"
with 10 gallons, a filter and only 3 small newts shouldn't cause an amm. rise. I've had 30 easterns in a 20gL half full (10g water) with a small filter and never had a problem.
What to do? Daily-weekly (depends) 50-100% water changes, amm. REMOVING chips in your filter (fresh weekly), they also have amm. lock liquid for fish that might work for newts too, but never tried on sallies myself. This basically makes the amm. non-toxic BUT will still show up on your tests.
Check for those blackworms though.
hope I didn't blab too much.
Steve L
p.s. LFS's have all kinds of amm. reducing items. If it's really bad , do 100% water change, since its just newts and not fish.
