Can I Put Mollies In My Cycling Marine Tank?

[fishlette]

if this is possible, how would i go about acclimating them?? pH is 7.2 in FW tank and 8.3 in the SW tank

 

[FishHobbyist1564]

Well it is kinda hard getting them used to a cycled marine tank... so i dont think it would be that great if you tried getting them used to a cycling marine tank. Therefore, i think it would be best to wait (unfortunately)

 

[fishlette]

Well it is kinda hard getting them used to a cycled marine tank... so i dont think it would be that great if you tried getting them used to a cycling marine tank. Therefore, i think it would be best to wait (unfortunately)

thats odd!!! ive heard and read in a few places that mollies are often used when cycling marine tanks...was even told so by my marine guy but he didnt tell me how you would acclimate them. it seems strange that i can keep mollies in TRUE brackish water but couldnt acclimate them to marine i mean, mollies originate from marine environments and i know they have been mainly bred in FW but it still seems odd to me that it would be HARD to acclimate them

so its all well and good what was said but still doesnt answer the question of how would you go about introducing a molly to a marine tank. this i would like to know as it will be some months before i add my fish and corals and would like to keep some of my guys in there until i get fish

 

[theotheragentm]

Most brackish fish can be acclimated to true saltwater conditions, but it involves small, increased dosings of salt until the salinity reached is true marine water. If the tank is cycling and already marine conditions, you have little chance of acclimating the fish. You're just dumping it into a completely different environment and are likely to kill the fish from shock between the two environments.

 

[andywg]

Most brackish fish can be acclimated to true saltwater conditions, but it involves small, increased dosings of salt until the salinity reached is true marine water. If the tank is cycling and already marine conditions, you have little chance of acclimating the fish. You're just dumping it into a completely different environment and are likely to kill the fish from shock between the two environments.

This is close, but not quite correct.

Truly Eurahaline fish (those that move around estuaries into different salinities) can be taken pretty much from FW into SW with less than an hour acclimatisation.

The biggest problem when changing fish from FW into BW (or SW) is usually the fact that the fish are already in the tank with a filter. Above a SG of around 1.005 the FW bacteria seem to die off to be replaced by a different strain which works in BW. It is because of this that you have to be careful when raising the salinity in the tank, rather than for the fish.

In this case, I would suggest taking the Mollies and putting them in a bowl of the FW tank water. Then set up a drip with airline from the SW tank so that it drips into the bowl at a rate of about 1 drip per second. Every so often you will have to drain half of the water out of the bowl. After a few hours test the temp, pH and the SG of the bowl and compare to the marine tank. Once they are all identical, the mollies should be fine to be netted out and put in the marine tank.

 

[Miss Wiggle]

yeah it's pretty common practice to use mollies to cycle marine tanks (although not a practice i wholly condone)

as andy said, a careful drip acclimitisation should be fine

 

[fishlette]

yeah it's pretty common practice to use mollies to cycle marine tanks (although not a practice i wholly condone)

as andy said, a careful drip acclimitisation should be fine

its not so much to cycle the tank as i have live rock, some tiny hermit crabs and a couple of urchins in there. its more to have some fishies in there while i wait for the marine fish etc i figure considering they are suitable for SW then there should be no harm letting them hang out in there for a while. im sure they would enjoy the room for a while

im assuming the same drip acclimitisation would be used when returning them to the brackish??

 

[Miss Wiggle]

drip acclimitise both ways, also you should use the same method when acclimitising your marinefish when you get them so it's good practice!

do remember though that the changeover in conditions however carefully done will cause some stress to the fish, if you're just talking about putting him in for a couple of days, maybe a week or two then i wouldn't bother, only do it if it's reasonably long term to give the fish a chance to adjust and not stress him out being caught repeatedly.

 

[fishlette]

drip acclimitise both ways, also you should use the same method when acclimitising your marinefish when you get them so it's good practice!

do remember though that the changeover in conditions however carefully done will cause some stress to the fish, if you're just talking about putting him in for a couple of days, maybe a week or two then i wouldn't bother, only do it if it's reasonably long term to give the fish a chance to adjust and not stress him out being caught repeatedly.

yeah i understand this. will prob be for a few months