3 Mollies Gone In 2 Days

[kyluh]

Hi all =)

I am new to posting (hopefully I found the right spot!)and a beginner level aquarium keeper. I've read as much as I can to prepare myself for keeping an aquarium, but these last two days have been hard for my fish. I've posted my problem and my aquarium stats after..


We started our tank off about a month ago with 3 Sunburst Platys, after a week they were doing well enough and the water tests were within range so we brought home 3 Dalmatian Mollies. Everyone got along great.

FAST FORWARD: Monday night I came home and one of the female mollies was exhibiting strange swimming behavior (wasn't able to keep balance or stop itself in time to avoid collisions with walls or decor) and hadn't really eaten all day. It stayed at the bottom of the tank, in a corner. When I checked up on it again, it was vertical with it's head toward the substrate. After a while, it went belly up and was still breathing. I called the PetSmart where I purchased the fish and I was told to euthanize All other fish acted normally after that, except the other 2 mollies who had just lost their swimming buddy.

The next day we went back to the store to get another dalmatian molly to make the other two happier. When I checked on the new molly the next morning, she had developed some strange substance on the top of her head (brown & muddy in coloration, I'm sorry I have no pictures). In addition to that, her eye had been covered in some weird gunk, sort of glazed over is the best way to describe it. When we took her back to the store, the associate said he had never seen anything like that before and that their black and dalmatian mollies had been having trouble lately. He said it would be okay to replace it, we SHOULDN'T have any problems. We decided to go instead with getting 2 balloon mollies because we were told they school together with the dalmatians. We got them into the tank and they started socializing well with the other fish. Then later that night, our second to last dalmatian molly in the tank died. It started exhibiting the same behavior as the first molly (strange swimming patterns, wouldn't eat, vertical, hiding), but it went much quicker than the first.

So 3 mollies in 2 days. I'm not sure really what to think, because as I'm typing this out, I'm realizing more and more that there are probably some things I probably shouldn't have done. I really need to know if my other fish will be affected by this (I know the associate said it was a problem with just their dalmatian mollies, but he never said what the problem was). I would appreciate any feedback on the conditions of the tank as well (should I change anything?)



Tank size: 20 gallons
pH: About 7.5 I think. Slightly above neutral range but below alkaline.
ammonia: 0
nitrite: 0
nitrate: 0
kH: 100
gH: 75 (soft)
tank temp: 80 F


Volume and Frequency of water changes: Since I got the tank a month ago, I've done a 10% water change every week. I am about to do my 25% monthly change, but would like advice before I start that.

Chemical Additives or Media in your tank: Top Fin Water Conditioner, Top Fin Bacterial & API Aquarium Salt (I've followed all dosage instructions to a T)

Tank inhabitants: 4 Sunburst Platys, 2 Balloon Belly Mollies & 1 Dalmatian Molly

Recent additions to your tank (living or decoration): 2 Balloon Mollies

Exposure to chemicals: None

Hopefully I've given enough information. I will try to post pictures if I can.

 

[Staxx]

why are you adding salt ?

im not really sure why your fish died to be honest either. i had a cory cat die on me the other day for no reason either.

 

[Joanne_]

I can see there being a problem with your tank sitting at zero for ammonia, nitrite and nitrate.

It looks like your tank is not cycled. Strange that the ammonia reading is zero though ...

Ammonia should already be in your water as the fish themselves are releasing this. The good bacteria will slowly start to grow and convert the ammonia to nitrite then nitrate.

While you are cycling the tank you will get an ammonia spike, then a nitrite spike then nitrate will be the next to go up in the readings. In the end, you need to get the ammonia and nitrite readings down to zero and nitrate at a low reading.

Once the water tests zero for ammonia, zero for nitrite and nitrate is rising, it means your tank is cycled.

Also, once your tank is fully cycled keep an eye on the nitrate levels. Check it every 1 - 2 weeks to make sure it isn't over 50ppm. If it is, it means you need to do a partial water change to bring it back below 50ppm.

 

[Ruskull]

Sorry for your loss. I would do a huge water change, or maybe (2-3) 50% water changes so you don't stress the fish out that much. I wouldn't add any fish and I'd keep an eye on them for the next week or so.

 

[kyluh]

Staxx- I had originally not added the salt to the aquarium, but after doing some research and talking with the employees they said that the platys and mollies needed to be in brackish water as it would improve gill function and that they do better with a little bit of salt. Should I stop adding them?

Joanne- I thought it was strange as well. I have a home test kit and also take my water in once a week to the store to get it tested. So far, everything has shown up within normal range, unless they're lying/ incompetent (which is what I'm starting to think...) We had our tank up and running for about a week before we started adding fish. Thank you for all of that information, your breakdown has explained it a lot better than some information I have been finding on cycling.

Ruskull- Thanks for that advice, I was about to do a 25% but will increase it now.

Thanks for such quick responses, I really appreciate it!

 

[Joanne_]

That's okay Kyluh. If you need help with what I typed above feel free to ask. But you should definitely have a reading higher than zero for at least one of three. You might need a new kit ?

I use the API Freshwater Master Test Kit and it has been working fine for me. Is your test kit old ? It could be expired and giving incorrect readings.

 

[kyluh]

That's okay Kyluh. If you need help with what I typed above feel free to ask. But you should definitely have a reading higher than zero for at least one of three. You might need a new kit ?

I use the API Freshwater Master Test Kit and it has been working fine for me. Is your test kit old ? It could be expired and giving incorrect readings.

I currently am using Tetra Easy Strips, so it reads everything except Ammonia, which is why I bring it into the store to get it tested as well. I also just read that the strips can give pretty inaccurate readings. Do you know if that's true? I'm thinking of investing in a better one anyway. Oh and not old. Purchased along with the fish about a month ago.

 

[Ruskull]

If your tank still needs to be cycled you're in for many more water changes or many more deaths. Def. get a better handle on your water readings, tanks don't magically become cycled after a week of running with no fish or ammonia added to start the process.

One type of bacteria turns the ammonia into nitrite, & one type turns the nitrite into nitrate. You lower the amount of nitrate by doing weekly water changes, usually of about 10-25% depending on how many fish you have & how often you feed them, etc.

 

[Joanne_]

I would not use test strips. Definitely recommend going with liquid test kits
Again, I use the API Freshwater Master Test Kit which is really good

 

[kyluh]

If your tank still needs to be cycled you're in for many more water changes or many more deaths. Def. get a better handle on your water readings, tanks don't magically become cycled after a week of running with no fish or ammonia added to start the process.

One type of bacteria turns the ammonia into nitrite, & one type turns the nitrite into nitrate. You lower the amount of nitrate by doing weekly water changes, usually of about 10-25% depending on how many fish you have & how often you feed them, etc.

Oh my, I thought I had done some intensive research before I even bought my tank- I have a lot more to learn! I'm definitely okay with doing the water changes, just want these little guys to do alright.

Again, thanks to everyone for their advice!

 

[Dazzler666]

It seems quite likely that maybe the mollies were infected when you got them from the LFS.
as already stated, DO NOT add any more fish just yet. Waut a few weeks & monitor the tank to see if it is cycled & your fish incase your other fish have been infected by some bacterial disease.
Water changes, water changes & water changes!!! Can't do too many water changes. When any signs of sickness, first thing is test water & water changes.
Definitely get a liquid test kit, I use API Master kit & they are far better than strips (I used to use strips when I first hit into the hobby but they are really in-accurate).
Regards salt, I'm aware that black mollies require salt to prevent white spot Type appearance but I can say that I've had Dalmatian mollies & still have one that u bought around 18 months ago & 4 three month old fry & I've never added salt & touch wood I've had no problems. If you are worried you could just give your mollies a salt bath every few months if memory serves me correct!! Personally I'd be careful though as cant imagine most tropical fish bring to keen on salt, well otherwise they'd be saltwater fish!!
Hope you get things sorted in anycase.