It's some type of algae, I'm not sure what though.
Glad there is no traces of ammonia in your tap though, that's a good start although makes it more difficult to decide what the heck made your ammonia spike so high lol. I mean, it could be the potting soil and the snails combined maybe, idk. And the tank wouldn't smell if you had dead snails in there, especially if the girl's ate them. I've had plenty of dead snails and they only smell after you take them out of the water, my water always smells fine though.
I really think you need to use the antibiotics on them, make sure it's the right kind though. Try to use a broad spectrum one like KanaPlex, I like KanaPlex since it's very easy on their system as well and doesn't stress them out as much as Maracyn will since it's older, it also may not have an effect on the disease. Keep the girl's QT'd for at least another two weeks though just in case they show signs of the illness.
Ok good, glad it wasn't something bad. After doing my mass cleaning tank change last night, I let it sit over night and just measured it this morning. My NH3 levels are down, but still present around .5-1ppm. I have a hard time believing plant matter contributed that much NH3 into the system though. Would aeration of the soil play a role? When scaping this tank I put a bit much soil down, a little more than 2" and aerate as often as I can, but know I miss a bit. I fear one of the better ideas would be to re-soil the tank.. which would suck, but this time I could sift the soil and clean if prior and also get rid of any potentially dead nerites buried into the soil.
Like I said I've got Maracyn 2 on the way and Methylene Blue as well (want to save this for very sick betta's) but I can order Kanaplex, I've heard very positive things about it, it would just take another two days to arrive. Lilnaugrim, if you think that's what I should do I won't hesitate to do it. I can do two weeks, I have no problem with that but at this point, if you were me would you buy another tank? I just know the girls hate they're cups. I can get a 10 gallon locally for like $20 and get the heater on Amazon for $20, its really not so bad. The air pump and the rest is very cheap as well, and I could just separate them up. Just a thought, if you think the cups are ok I'll stick with them, its just with the other AQ I could treat them all with anti's, and keep them at an optimal temperature all the time. I could separate them with that eggcrate stuff. They'd each get two gallons :3
I would think that getting a 10 gallon to use as QT right now would probably be the best idea, not only for the girls but for you as well; it's going to take off quite a bit of stress. You'll still need to do water changes according to the medications but it might be easier and less stressful on the girl's as well. Also, have you looked at Wal-mart or anywhere they sell just the tank? All you need is the tank and a heater and of course the divider's, but the tank should only be 14.99 generally if it doesn't come with other stuff. You can use a filter if you want, just make sure to take out the carbon in it so it doesn't remove the meds.
As far as soil getting gas bubbles, it does happen but very rarely will it but that horrible it will cause a spike of ammonia to go up to 6-8ppm! It would have to be a very large bubble and you would notice a horrible sulfur smell in the room where the tank is, if you don't smell bad sulfur then you're set and it wasn't a bubble.
Yeah, I do still recommend KanaPlex. You can start treating with the Maracyn while you wait. If you don't, I don't think using salt will be a good idea though, it's just more added, unnecessary stress for them is all. And besides, too much of it can cause severe damage to the kidney's/liver, causing them to go Dropsy mode and die I've had that happen before unfortunately.
I really have no idea honestly, the only thing I can think of would be not rinsing the substrate but that's so moot it isn't even funny, it wouldn't effect the tank at all and definitely not after all this time. All I can think of are the two missing snails which could just be hiding but if they haven't turned up by now then I'm thinking it is possible you buried them by accident and they just never made it up :-/
Here are my three options; I have AQ salt on hand, and I've been treating accordingly because its better than nothing (I thought) but they show no signs of problems, besides slight inactivity due to small cups. My other option is the Maracyn 2 - It will be in the mail tomorrow and I can start treatment tomorrow night. My third option is KanaPlex - I just bought it and it will most likely be in next Monday. I'm willing to wait for the KP if you think its safe, I want to have it on hand as well though.
You're saying to stop treatment altogether with AQ salt? It sounds like it may be more damage than help.
I've rinsed substrate before - its nasty work but is worth it. I forgot to do it with my 20g, I'll do it when I plant this new 10g. There are so many plants and the snails blend in so well its not even funny. I'm about 80% sure they are either dead or were never in there to begin with. I guess the next best option is to re substrate the tank? I can do it, I'm just worried about uprooting all those now rooted deep plants, especially my Red Tiger Lotus!!!!!!!!!!!!!!
I've also got a heater on the way, going to get them in that AQ asap, probably at first all together and separated just so they have more space then I'll throw the heater in. I just know they hate those cups, and I do to. With the AQ, I'll be able to just siphon as well.
Yeah, KanaPlex is very safe and very non-stressful for the girl's.
AQ salt doesn't help for anything except Ich and sometimes Velvet if it's not too far along. What AQ salt is balance out their electrolytes (that part is good) but it also just invigorates their slime coat so they produce more which makes the old slime coat shed; thus knocking off parasites like Ich. But it does nothing for slime infections, columnaris, fungal stuff and other's. So yes, I think you should wean them off.
I don't really think you need to resubstrate your tank, you said your ammonia levels were coming down right? So that's good! Just keep an eye on them as the girls are in QT so that you can catch if it spikes again is all.
I noticed a few of the girls are kind of sitting on the bottom sometimes, fins aren't clamped though. I'm not sure if they are sleeping or getting depressed. Anyways, I ordered the KanaPlex. I'll discontinue to AQ salt, it might be why they are kinda sluggish. Glad to know I won't need to re substrate my tank.. even if a snail died, after a while the corpse would stop giving off NH3/rotting right? Will keep you updated, going to check NH3 levels tomorrow morning. Girls are quietly floating tonight :)