Tropical Fish Keeping - Aquarium fish care and resources

Tropical Fish Keeping - Aquarium fish care and resources (
-   Tropical Fish Diseases (

stephenmontero 05-23-2008 05:30 PM

All Mollies dead in 40 gallon tropical aquarim tank. I know i know i hear it over and over agian these fish are brackishwater fish and well there was some salt about 3 table spoons in 40 gallons of API aquarim salt. anyway i did a water change today i did a 10 gallon swap cause the water looked a little cloudy. that happened 2 hours ago now the water i put back in was aged 24 hours and was the same temp as the tank and had tertra aqua safe decholrinizer in it. i kept the water warm using the same brand stealth heaters as in the tank to ensure no difference and i checked before putting the water in. so anyway 2 hours after the water change i go down stairs and 4 out the 6 of my mollies are dead. the other two are not looking so hot the rest of the tank is fine and acting normal
2 angels
2 paradise fish
2 swordtails
4 platties
2 black skirt tetra's
4 cories

water parmaters
nitrate 20
nitrite 0
ppm hardness 50
ppm alkalinity 120
ph 7.1
temp 78
salt 1 tablespoon per 10 gallons

tested with api liquid master

sorry this post is so long i wanted to be priciese wat should i do with the whole tank i need suggestions all the fish looked normal when they died i looked at them carefully no outside signs they were having a problem

the mollies that died were
2 white sailfin mollies (male and female)
1 sunset mollie (female
1 ballon body (female)

the 2 that are still alive
1 sunset mollie
1 balloon body molly

ill post pics in a minute

please tell me what i need to do

fish_4_all 05-23-2008 08:34 PM

Well from what you have said my first thought would be you need to get a hydrometer. I made this mistake when I used to add salt and killed a few fish with a water change.

Large swings in salinity can be the worst thing for them. A hydrometer will help you make sure that the water you are putting in is the same salinity as the tank or close enough not to shock the fish.

Salinity for brackish: 1.005-1.010

stephenmontero 05-23-2008 08:39 PM

i guess but i used the same amount of salt as always plus wouldnt the swing would have affected other fish

fish_4_all 05-23-2008 08:56 PM

One would think so but I have killed swords in a tank I added salt to and it didn't take out the feeder guppies.

All I know is I won't add salt on a regular basis again unless I have one, a teaspoon or tablesspoon just doesn't cut it.

I don't remember where I saw it but someone added salt with a tablespoon on a regular basis. It worked for like 4 months but one day they added the salt to the buckets and then added during a water change the water and killed a tank full of mollies. Come to find out the salinity in the tank had almost gotten to levels you see in salt tanks and the added water was a lot lower. It was a mollie tank so no other species in that one.

Just so we get this right, are you talking about reef salt or are you using fresh water aquarium salt that is actually used to treat prasites and is not recommened for brackish tanks? I don't know why but have not heard many that recomend it.

stephenmontero 05-23-2008 08:59 PM

its api freshwater salt it says good for brakish water fish this is only my second add of salt

herefishy 05-24-2008 09:25 AM

When I add salt to my livebearer tank it is at the rate of 2Tablespoons per 5g of water. So, in a 40g tank, if starting from ground zero, add 8 Tbsp. of salt. It should be Salt for reef tanks and not aquarium salt. Aquarium salt is for medicinal use and adds many micro elements to the water and raises salinity only slightly. I actually raises hardness more. I do not use reef salt. Ad the tanks are NOT brackish. And if you are wanting to go brackish, as suggested, I would get a hygrometer or a salinity difractometer.

Now, looking at the mix of fish in the tank, one cannot have a brackish tank with fish such as paradise fish and tetras. This fish will not tolerate such conditions. So, a family tank of livebearers would be best wit hnone of the other fish in their tank.

Temp may also be high for the livebearers. I keep mine around 72-74 degrees. I word of caution here. At such low temps, the possibility of ich increases. Keep an eye out for any outbreak.

So I guess that my suggestion is to keep the livebearers in a tank of their own. Get the equipment suggested. Another thing that I might do is a 50% water change 2-3 times over the next 7-10 days. I would then measure the tanks salinity and add sea salt accordingly as I did my regular water changes. Increase the salinity gradually.

stephenmontero 05-24-2008 09:29 AM

well all the mollies died over night so now its just all those other fish wat do u think i should do?

herefishy 05-24-2008 10:13 AM

Unless you are dead set on having livebearers, I would stock the tank using the fish you have left with similar, compatible fish.

Who said keeping livebearers was easy, huh?

Amphitrite 05-24-2008 10:15 AM

I would do a series of large water changes to dilute the salt in the tank, keeping a very close eye on the water parameters.

How long had you had the mollies for Stephen?

stephenmontero 05-24-2008 10:17 AM

a month

All times are GMT -5. The time now is 10:40 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome