HELP ! Swordtail(s) with bloated, white belly

[Scott F]

This morning I awoke to find one of my swordtails had died. Upon inspection I notice that 3 of the other females had white, bloated belly and had a very hard time swimming and were hiding in my plants and where t would be hard to get to them.

Now, I'll admit, I've never seen a pregnant fish ( and yes, there are two males in the tank) so I took the three out that were looking similar and put them in a container in case something else was going on.

One was having a very hard time swimming and was near the top. The other two went to the bottom and just stayed there.

Water parameters were PH 7.6, Zero amonia, nitrite and nitrate as of yesterday.

Will go home and re-check tonight but not sure what could be wrong. I did introduce a new snowball pleco, and 5 hatchet fish yesterday but they all seem to be getting along and not having problems.

The only other thing is that I have an established 10 gal tank that I could move my neons from into my 40 and make the 10 gal a hospital tank. Good idea ?

Up against a wall here and could use some help. I cannot afford to have my other fish be getting sick

 

[Chronos313]

No nitrates? How long has your tank been setup? What type of cycle did u do? How big is your tank?

 

[Scott F]

Nope...no nitrates, or if so very little. My API test comes back yellow with a tinge darker than the base reading. Tank has been set up for three months. Went with a normal cycle using shrimp for a base watched the ammonia spike, the nitrites rise and the nitrates take over. Took about 4-6 weeks.

Haven't had an issue in 3 months with it until yesterday. Had to Euthanize 2 of 3 swordtails though. Remaining fish are all looking well this morning, they got some daphnia last night and are going to get a fast of a couple days.