Frequent Molly Deaths, What Is Happening?

[jakeyman_i_am]

I have a 20L tank with a submersible pump, a submersible heater, a 10 inch air stone connected to a Whisper20 pump, and a 30 inch light. I had the tank up, and at 75 F for about a week before I dropped in 6 Mollies, 3 black, 3 white. They lived very happy and it turned out that one was pregnant because she had fry in my tank. However, not long (two weeks or so) after the tank was set up they all died. Not all in one night, over the course of a week. I pointed to the new plants I had just dropped in the tank after setting it up.

I pulled the plants out, drained the tank, refilled with tap water.

After a week or so the tank was back to temp and real plant free. I had noticed a few snails ‘running’ around in the tank, but figured that it was no problem, so I restocked the tank with 6 more Mollies. That was a month ago and right now I have 2 remaining Mollies, one male and one female. The rest have died. The only long lasting survivor is a ghost shrimp, which has been with the tank since the first day of setup. Both batches of Mollies have been from different stores with different suppliers, and have been properly introduced into the tank.

I now have probably 200 snails in the tank. Could it be that the Mollies are overeating by eating the snail eggs? I have a piece of lettuce in the tank right now, rocked to the bottom. I hear on another (less friendly ) forum that this works because they will all attach to the lettuce, then allow me to pick them up out of the tank.

Also, my filter is for a 40 gallon tank and makes allot of current in the tank. Could that cause stress and thus death?

I have some plans to increase my rate of life here. First of all, when these mollies die (or if they don’t for a few days.) I will take down the tank and BLEACH every square inch of stuff, then rinse it, bleach it, rinse it, and rebuild it. I will fill it with distilled water, and instead of using my cheap submersible filter, I will get a bio wheel. I need to replace my hood because it is for reptiles, and it corroding because of the evaporation. And, I am going to try another thermometer to prevent the chance that the temp is off.

I have tried to describe my situation to the fullest detail here, but if I missed anything please tell me. I just want my Mollies to live and breed!!!

 

[stang1]

People will really need to know your water stats in case that is part of the problem.

 

[jakeyman_i_am]

People will really need to know your water stats in case that is part of the problem.

I am a newb to the whole water stats thing, and fish tanks in general, but while I am at the pet store tomorrow I will pick up some tests. Thank you for your reply!

 

[stang1]

No problem. It might be worth taking a water sample with you as well so your lfs can check it for you.

 

[jakeyman_i_am]

No problem. It might be worth taking a water sample with you as well so your lfs can check it for you.

Do you see anything else (the snails, ext) that could cause this?

 

[stang1]

I'd be very surprised if it was the snails. How long do you leave the lettuce in for?
The only reason I ask is because a little while ago I forgot about a piece of cucumber I'd left in my guppy tank, it sat there for three days. I was also trying to get rid of snails, unsuccessfully. I checked the water and the nitrite had spike dangerously high. I ended up moving the guppies to a spare tank and had to change the water and pretty much start the cycle again. I ended up stripping it down just to get rid of the snails! Don't worry, I'm not suggesting stripping your tank because hopefully someone may be able to help with the snail problem.

 

[jakeyman_i_am]

I'd be very surprised if it was the snails. How long do you leave the lettuce in for?

The forums said 'overnight.' So, I am taking that as 12 hours. I will let you know how that one goes. About 5 have passed now and still no takers that I can see from here. The only reason I say the snails might have a part in this is the fact that I have seen the Mollies picking at the eggs stuck to the side of the tank. I have no idea if they are eating the slime the eggs are in, or the eggs themselves. I know that a suddon outburst of snails usually means that the tank was overfed, and I know the snails got into the tank on the live plants, both of which mean that I messed up. LoL. Either way I am trying to avoid using 'Hadasnail' which my local pet store fish guru suggested, as a last resort. He said that soft water (which this area is known for, I guess) has a tendancy to let the chemical in the 'Hadasnail' kill or sicken the fish... Not cool, I like shortcuts...

 

[stang1]

I'm sorry I can't be of much help to you. You'll know a bit more when you get your water tested.
And you haven't messed up, we all have to learn, sometimes the hard way.
I brought plants that I didn't rinse off, hence the infestation! We've all done it at some point.

 

[jakeyman_i_am]

I'm sorry I can't be of much help to you. You'll know a bit more when you get your water tested.
And you haven't messed up, we all have to learn, sometimes the hard way.
I brought plants that I didn't rinse off, hence the infestation! We've all done it at some point.

You were a great help, I now know to test the water. Thank you!

 

[starrynightxxi]

20 liters works out to about 5 gallons. definately not big enough for mollies, which can grow 3-4 inches (i believe, you'll have to check the profile on them). Also, this is a new tank, which means it hasn't cycled yet, and THAT means that there was far too much ammonia and/or nitrite in the tank for the mollies to handle.

If your filter is for a 40 gallon tank, why don't you get a larger tank? a 5 gallon is just too small for a large, active fish like mollies, and you will also have room for more mollies and their fry which are inevitable unless you have only males. [edit] also, though many beginners want to start small, larger tanks are actually best because they are much more forgiving regarding water quality fluctuations whereas small tanks can take a wrong turn and crash before you have a chance to do anything about it.

when you test the water, you'll want to test for PH, ammonia, nitrites, and nitrates according to the directions given. Get a test kit with glass tubes and chemicals rather than strips as they can be innacurate. Also compare those numbers (specifically PH) to the LFS tanks because PH shock can also do a fish in.

FINALLY, when you say tap water, do you mean wate straight out of the faucet, or water that you have treated for chlorine and chloramines? If you mean water straight out of the tap, you also need to buy a dechlorinator from the pet shop (one whic also will remove chloramines) as these things can ALSO kill fish.

my solution:
1. buy a bigger tank
2. buy dechlorinator (if you don't have it already)
3. buy a test kit
4. read up on cycling (check the FAQ and the beginner's forum) before buying anymore fish

good luck


[edit, again] one last note, mollies will be at their best with salt in their water, meaning marine salt, not standard aquarium salt which won't do anything in particular for them. Other folks can explains that part of it to you, I don't know anything about salt beyond what I just said

 

[nmonks]

As starrynightxxi says, mollies are big fish. The smallest varieties (known as "shortfin mollies") get to about 6 cm, with females being bigger than the males. The larger varieties (the "sailfin mollies") are anything between 10 and 20 cm in length depending on the species or hybrid. Virtually all the stuff in shops are hybrids and stay around 10-12 cm, the females a little larger than the males. Wild Mexican sailfins are huge, the males around 10-15 cm, and the females 18-20 cm.

As for salt, there's a pinned topic here. Yes, some people keep them without salt, but lots of people have terrible luck trying that. It seems to be about 50-50 in terms of mollies needing salt. Since adding salt will do no harm to mollies, and 50% of the time will save their lives, it seems to me a no-brainer. Go buy some marine aquarium salt mix and add around 3-5 grammes per litre.

It's an interesting point for discussion whether the salinity is the helpful thing or the increase in pH and hardness that comes from using marine aquarium salt mix (not tonic salt or cooking salt). It's probably a bit of both.

Cheers,

Neale

 

[HODDY]

hi,You could try getting a bigger tank and a test kit.Waai for about 2-3 weeks and then add fish.I would suggest adding a little salt.What are the dimensions of your tank?

 

[jakeyman_i_am]

20 liters works out to about 5 gallons. definately not big enough for mollies,

I ment 20 long by 20L. Sorry I didn't see that one comming. It is a all-glass 20 gallon long (30 inch) tank.

Sorry guys!

 

[jakeyman_i_am]

I have allot of things that I plan to test and try.

1. Clown Loaches to help control the snail life. Even if this has nothing to do with the actual problem, it will give me peice of mind.
2. Testing the water.
3. Maybe bringing down the whole tank.
4. Using distilled water

About number 4 here, we live in the country, and thus have well water. The water is awesome here, but like I said is soft already and we have a water softener. Could these two thing together cause these issues?? When I take the tank back up after the full blow away I will use just water out of the cold water faucet, because the cold water line at our house is not treated by the softener.

Anyone think this would help?

Thank you for all of your help!

 

[HODDY]

i put warm water in my tank(same temperature as the tank)Why dont you try geting some danios they are alot hardier than mollies and will help your tank.A clown loach might get to big for your tank.