What's up with my platies??

[petunia100]

I have two female platies who are pregnant. They both have gotten whitish scales. It doesn't look like ich, I don't know if it's a fungus or just stress from being pregnant. It looks like the scales have lost their color, it is not "hairy or furry". Today the female who has been pregnant the longest has developed some brownish in the white areas. I have had diatoms in my tank recently, not terribly badly though, weirdly it kinda looks like diatoms. Both fish are active and eat, although the larger female has started hanging out behind my large plant more and is acting shy. I think that she's close to having her fry. I just tested my water parameters and the ammonia is 0 ppm, nitrates are <5 ppm, and the nitrites are 2-5 ppm. I have been having problems with my nitrites during my cycling and have been doing 30% water changes every other day during the last week to help out, the ammonia has come all the way to the 0 though so that's good. Is this problem with the scales something I should treat or is it from being stressed and "pregnant". All the other fish in my tank (20gal) are acting great, and do not have this discoloration.

[petunia100]

another picture of the larger female

[petunia100]

[petunia100]

The patches are located on the necks of both the platies, and tend to be on one side more than another.

[Menagerie]

Those nitrites are a problem. Do 30%PWC everyday to bring them down. In the meantime, add a bit of aquarium salt to bind the nitrite molecules, so the fish are less affected. Also add in Melafix to help.

[petunia100]

I've been adding in salt, but maybe not enough to make a difference, about 2 tsp per gallon. What would a better amount be?? Will the fry be affected by melafix? Is melafix for bacteria or fungus? I have maraycin II on hand would that work? Thanks for the help!

[Menagerie]

Melafix is a good, gentle med. If the fish are doing well, stick with the amount of salt you already have, PWC and Melafix. If things go downhill, then pull out the more powerful meds

[TankGirl]

Nitrites aside (nitrite should not be present at all, so the cycle needs to be completed, as you know) lightening of the belly as she gets closer to dropping her fry is normal. I can't promise, but she looks pretty normal to me in terms of lightening of the expanded belly. It seems to be more evident in the orange/gold livebearer varieties.

[Menagerie]

lightening of the belly as she gets closer to dropping her fry is normal

I just learned something new!

[smallfry]

Hey Petunia,
Having observed many pregnant platies of the same color as yours, your pregnant platys look perfectly normal in coloration. As has been said, it is normal for their coloring to look pale/patchy, particularly around the stomach area. Think of it as fishie stretch marks.....after they have the fry, the coloration should go back to normal and the patchiness will go away....the brown spots in the stomach area are little babies!

[petunia100]

I've gotten the melafix to treat the tank. It recommends removing the carbon filter if possible, with this or the melafix affect my "good" bacteria? I'm already having problems with my tank cycle and I don't want to make it worse. I've been doing 30% water changes every day and it's still at about 2ppm. Will melafix have any affect on the fry? (Still waiting but they should be here any day.) :P

[TankGirl]

Melafix will not interfere a bit with your cycle, no matter what stage it is in.

[petunia100]

so I should take the carbon out but leave the biofilter in? TIA

[TankGirl]

Yep, you should not be using carbon if you are using Melafix, but if the carbon is more than a week or so old it is not making any difference one way or the other now, so leave it be - it is harboring good bacteria as well at this point (it becomes clogged rather quickly and loses effectiveness after about 5-7 days).