Bumblebee Gobys!

[CPQ]

Hi,
I originally posted this in the tropical forum and was told to come here.

I've seen some bumblebee gobys in my lfs and having looked them up on the internet am completely confused. Some people say they're freshwater and others that they're brackish. I knwo they're kept in freshwater in my lfs but don't know if this is because they're doing something wrong (and trying to fob of brackish fish on people who just don't have the set up to look after them properly) or whether they are actually ok in freshwater!?

any help would be great.

Thanks

 

[Matty P]

There are two main types of Bumblebee Gobies, one type is purely brackish water and is intolerant of freshwater, the other one thrives in brackish but can tolerate the freshwater enviroment.

Brachygobius xanthozona:

This type has perfect unbroken black stripes and is best suited for brackish, but can tolerate fresh water much better than the other type.

Brachygobius nunus:

This type has broken banded stripes, and sometimes black spots or broken stripes. It isn't tolerant of a fresh water environment. This is also known as the Golden Banded Goby.

 

[CPQ]

lol - Well hello again Matty P!

Ok then - so basically if it's the first type they COULD be kept in freshwater but are happier in brackish! In that case I don't think I'll get any unless and until I can build a brackish aquarium (which will be a while since I'm still in the early stages of my latest project!).

Thanks for your' help!

 

[nmonks]

Matty P --

It isn't as simple as that. There's something like a dozen or so species in the BBG genus, Brachygobius. Telling them apart is, for the most part, impossible for the aquarist because of "species groups" containing several very similar-looking species. Scientists identify them by looking at dead specimens under a microscope, and need to count things like the arrangement of scales on the body. There's absolutely no way on Earth you can do this with a live specimen in a fish tank!

Anyway, the bumblebee gobies usually seen in aquarium shops belong to a complex of closely related species including Brachygobius doriae, B. xanthomelas, and B. sabanus. This Brachygobius doriae-group, as this species group is known, includes species that get to about 1.5 inches in length, which contrasts with the "dwarf" bumblebee goby group.

The dwarf BBG species group, including Brachygobius nunus and Brachygobius mekongensis, are less than half the size of the Brachygobius doriae species group. All this sounds simple enough, but the name Brachygobius nunus has quite commonly been applied to members of the Brachygobius doriae species group. Although the dwarf species aren't commonly traded, they do turn up periodically, but are never identified as such.

Another name that gets misused is Brachygobius xanthozona. This species is in fact extremely rare in the wild and is never, ever traded as an aquarium fish. All photographs of BBGs in aquarium books identified as Brachygobius xanthozona do so in error.

Does any of this matter? All BBGs will do extremely well in low-end brackish water (around SG 1.003-1.005). But many species are also found in freshwater, and all can be kept in freshwater aquaria without problems. Some species are also found in blackwater streams, with an acidic pH and virtually no hardness, where they are found alongside things like rasboras.

In short, BBGs are adaptable. In aquaria, keeping them in brackish water is possibly the ideal simply because the salt helps detoxify nitrite and nitrate. According to Schaefer (in Aqualog) the key advantage is you can fill a brackish water aquarium with live brine shrimp and let the BBGs feed on them all day long. The real problem with BBGs is food. Most specimens die because they starve to death, not because of water chemistry issues. These gobies are very difficult to feed, and when kept in freshwater communities simply don't get enough to eat.

Cheers, Neale

 

[CPQ]

Wow! Thanks nmonks!

OK so (sorry for being repetitive here) would you recommend that I got a couple or not!? I'd like some but obviously don't want to put some in freshwater if they would be much happier in brackish!

If feeding them can be difficult then I won't get them for about a month anyway (I'm working away at the minute and would muh rather be around to make sure they're feeding properly that leave it to other people - esp when they're first settling in). but at least that way I have time to start breeding live food for them.

 

[nmonks]

I personally *wouldn't* keep them in freshwater. My experience of keeping them in a soft/acid freshwater aquarium was that while they did OK, they seemed to be more prone to infections. All my specimens died within one year. That said, the infection that killed the gobies also affected two other goby species in the tank as well, and so may have simply come in with one goby and cross infected the others. In which case, water chemistry wasn't the issue. But I can't rule out water chemistry from being a factor.

Regardless, you want to keep BBGs in their own aquarium. They just aren't "easy" community fish. This being the case, you may as well keep them in slightly brackish water. It adds little to the cost (10% seawater salinity is plenty, so the cost of the marine salt mix will be trivial) and might improve their overall hardiness. Certainly, if you're inexperienced with gobies, keeping them in a small (10 gallon) tank with slightly brackish water and an air-powered filter means you can throw in a bag or two of live brine shrimp every week and basically leave them to it. Easy peasy.

On the other hand, if you're an experienced goby keeper, and have kept and bred other goby species, so know how to get suitable small live foods into your gobies twice a day, every day, then by all means try them in freshwater. Provided you feed them properly, keeping BBGs in freshwater rather than brackish won't kill them. You *can* wean them onto frozen foods reasonably easily (I've found small bits of seafood plus bloodworms works well). But flake is, as far as I know, never accepted.

Cheers, Neale

Wow! Thanks nmonks!

OK so (sorry for being repetitive here) would you recommend that I got a couple or not!? I'd like some but obviously don't want to put some in freshwater if they would be much happier in brackish!

If feeding them can be difficult then I won't get them for about a month anyway (I'm working away at the minute and would muh rather be around to make sure they're feeding properly that leave it to other people - esp when they're first settling in). but at least that way I have time to start breeding live food for them.

 

[CPQ]

ok - well I've never had goby's before so i think from the sounds of it a species tank is the only way forward if I want them. I'm in the middle of my latest project at the minute so I won't be starting another for a while but at least I know how to keep them now when the time comes. a brackish tank could be pretty cool ... hmmm ... lol.

Thanks so much - you've been really helpful!

 

[nmonks]

BBGs *are* very cool, and a lot of fun to watch. A 10 gallon tank with a bunch of shells for them to explore, an air-powered filter, and a 50W heater is all they need. Put the tank by a window sill so you get some green algae growing, and before you know it, it'll look like a little rock pool. Since these gobies don't jump, you don't really need a hood, though a simple piece of glass or perspex over the top would be a good idea.

Once everything is settled in, you can add some shrimps, and the result would be a very cool low-cost aquarium full of fun things to watch. Most shrimps tolerate low salinities very well, even if they're nominally freshwater species. Likewise for Nerite snails, which are much more fun than regular snails.

Cheers, Neale

ok - well I've never had goby's before so i think from the sounds of it a species tank is the only way forward if I want them. I'm in the middle of my latest project at the minute so I won't be starting another for a while but at least I know how to keep them now when the time comes. a brackish tank could be pretty cool ... hmmm ... lol.

Thanks so much - you've been really helpful!

 

[Matty P]

Sounds like a lovely set-up, cheers neale