Says Guppies Can Be In Marine Water!

[Tokis-Phoenix]

One common decision on whether conditions are suitable for a fish are whether it breeds or note. In regard to this I noted in an abstract:

Females that stayed in 150% sea water (58.5%) for 30 days had embryos in their gonads.

J. Chervinski (1984) Salinity tolerance of the guppy, Poecilia reticulata Peters Journal of Fish Biology 24 (4), 449–452.

I think the problem with this though is that guppys will breed in pretty much any sort of water quality conditions, whether it is any good for them though is a different matter- I've known guppys to breed in drains or in tanks with shockingly high ammonia levels etc, so i wouldn't be suprised if someones managed to get guppys breed in marine conditions. While most aquarium fish won't breed if the conditions aren't exactly right and the future is looking rosey, guppys tend breed regardless of what the conditions are like, which is why breeding guppys tends to be no big acheivement in comparison to breeding other types of tropical fish etc.

I think the question about "can guppys be kept in marine conditions?" is kinda vague, i think "Is it good to keep guppys in marine conditions?" or "Will guppys live long in marine conditions?" etc would be better questions. For example i'm sure i could keep brackish bumblebee gobies in freshwater conditions for quite a while before they died off, but IMHO whether its any good for them is the main question.

 

[andywg]

I think the question about "can guppys be kept in marine conditions?" is kinda vague, i think "Is it good to keep guppys in marine conditions?" or "Will guppys live long in marine conditions?" etc would be better questions. For example i'm sure i could keep brackish bumblebee gobies in freshwater conditions for quite a while before they died off, but IMHO whether its any good for them is the main question.

Bad analogy. The BBG in the aquarium trade occur not only in FW in the wild, but in soft acidic waters too, so they are in fact a freshwater fish as much as a brackish (something backed up by experienced gobiologist Naomi Deventhal).

The Guppies can handle salt levels far higher than a number of marine fish can. They are doing ok for at least 1/24th of the expected life (going by your 2 year experience) and in the above research they were taking the salinity up quite slowly and dropping the fish back to FW in between 3 hours (100% SW) and 5 hours (150% SW) after 30 days at the salt level.

I have read of people having guppies for at least a year in SW (though this is uncommon as most of the people I know with SW guppies feed them up and use them as live food for SW preds).

 

[Tokis-Phoenix]

I think the question about "can guppys be kept in marine conditions?" is kinda vague, i think "Is it good to keep guppys in marine conditions?" or "Will guppys live long in marine conditions?" etc would be better questions. For example i'm sure i could keep brackish bumblebee gobies in freshwater conditions for quite a while before they died off, but IMHO whether its any good for them is the main question.

Bad analogy. The BBG in the aquarium trade occur not only in FW in the wild, but in soft acidic waters too, so they are in fact a freshwater fish as much as a brackish (something backed up by experienced gobiologist Naomi Deventhal).

The Guppies can handle salt levels far higher than a number of marine fish can. They are doing ok for at least 1/24th of the expected life (going by your 2 year experience) and in the above research they were taking the salinity up quite slowly and dropping the fish back to FW in between 3 hours (100% SW) and 5 hours (150% SW) after 30 days at the salt level.

I have read of people having guppies for at least a year in SW (though this is uncommon as most of the people I know with SW guppies feed them up and use them as live food for SW preds).

Ok so the analogys not that great, but do you agree that the best way to see how suited guppys are to marine conditions would be to get some guppys of good stock, and keep a record of their health, diet, genders and other things etc and ultimately how long they live for in marine conditions?

 

[andywg]

Ok so the analogys not that great, but do you agree that the best way to see how suited guppys are to marine conditions would be to get some guppys of good stock, and keep a record of their health, diet, genders and other things etc and ultimately how long they live for in marine conditions?

For a hobbyest, yes. Ideally you want to disect the fish and see if there are any noticeable effects on the fish at different stages.

However, in the absence of such information, the fact that they can survive conditions well in excess of marine levels (150-200%) for at least 30 days and then be taken back to FW within 5 hours makes me feel they have the osmotic equipment to handle extended periods in SW.

 

[Tokis-Phoenix]

Bad analogy. The BBG in the aquarium trade occur not only in FW in the wild, but in soft acidic waters too, so they are in fact a freshwater fish as much as a brackish (something backed up by experienced gobiologist Naomi Deventhal).

Actually on that note (not meaning to go too off topic or anything), but i've seen people referring to different varieties of bumblebee gobies. Is there just the one type of bumblebee goby, or are there different varieties of bumblebee gobys?

 

[andywg]

Actually on that note (not meaning to go too off topic or anything), but i've seen people referring to different varieties of bumblebee gobies. Is there just the one type of bumblebee goby, or are there different varieties of bumblebee gobys?

There are a number of species of Bumblebee Goby, though without a microscope and a penchant for counting scales, you aren't going to be able to get a species level identification.

Many people will talk of Hypogymnogobius xanthozona as a FW species, though this is probably referring to Brachygobius xanthzona which is almost never traded.

Most in the trade are Brachygobius doriae which does best in captivity in hard and alkaline water (which is why brackish water helps). However, most problems with these fish are almost certainly due to an inappropriate diet; these fish won't eat flakes and pellets and need bloodworm and daphnia etc (live or frozen).

 

[Tokis-Phoenix]

Ah thanks for the info/clearing that matter up for me .