Amblygobius rainfordi with ex-sunken belly 11/9/12 Hi :) <Borja> Just wanted to share a success report with an Amblygobius rainfordi. I picked the little one at my LFS on July. It had, as it's sadly usual with these fishes, a sunken belly. Needless to say, once added to the tank it begun to pick on my sand bed like crazy. It's a mature DSB, the tank has a surface of 110x55 cm, less than 30% of the sand surface is covered by rocks, and the grain size is 0.1 - 0.7 mm, the sand depth is around 10 cm. <Sounds good> The second photo was shot last week. Same fish of course. The third photo shows the rainfordi, the day it was introduced, together with a year-old resident, a female mandarin which was quite skinny when introduced, a year later, and apart from being really fat, has maybe grown more than 50% in length in one year. <Ahh!> Regarding its diet, I've observed it taking (of course) mouthfuls of sand and filtering them, and also picking at some algae and cyanobacteria growth I have on the side glasses, which I don't bother to clean, as (after examining samples on the microscope) they are full of copepods, small nematodes and other critters. However, it also filters and spits the algae, so I guess it doesn't actually eat the algae, but it eats the animals that live on it. Seems that a mature DSB should be considered mandatory for this species. Of course, it can be a risky addition. If the DSB is too small it can be too much of a predatory pressure... <Agreed> Neither the rainfordi nor the mandarin have even tried frozen food or pellets. They just ignore it. I've never observed them taking any of the food I add. The mandarin prefers to hunt on the rocks, and the rainfordi clearly prefers the sand, also spending some time on the glasses. <Some do, some don't accept other (prepared aquarium) foods> Best regards, Borja. <Thank you for writing in, sharing your experiences. Bob Fenner>

Brackish (?) goby for a Canadian I'm living in Canada and looking to purchase some brackish water gobies for my tank. I own a 30 gallon tank and looking to buy a butterfly goby and one I saw on Google known as the.....Amblygobius semicinctus.  If you have any of these fishes or know where I could get them. <Mmm, we don't sell livestock... and this fish, genus is better kept in full seawater. Bob Fenner>

Amblygobius phalaena: Tank Too Small? -- 04/08/08 Hello WWM-ers! <<Greetings!>> I have a 24 gallon JBJ nano cube and I do not have a refugium. I do 10% water changes every week and the water quality is usually excellent. I have a common clownfish (Amphiprion ocellaris), an orchid Dottyback (Pseudochromis fridmani), some turbo snails (6-7), a red legged hermit crab, and some pink xenia. While I was away this weekend my father bought me a male Amblygobius phalaena. <<I too have one of these, a great fish'¦excellent substrate stirrer/sifter, which is necessary to the long-term health of this fish >> He is about 4 inches. <<Will get larger'¦about 6' overall>> He looks fantastic, is surprisingly outgoing, and has been feeding voraciously for the past two days. <<Yup>> Over this short amount of time he has almost completely eradicated the filamentous algae in my tank, which I felt was somewhat abundant. <<Neat>> However, my research over the past few days have me concerned that my tank is too small and not mature enough for a fish with this kind of appetite. <<Mmm'¦the appetite can be supplemented'¦but yes, a mature larger system; with a deep bed of sugar-fine sand, would be a more appropriate environment. In addition, he has been biting occasionally at my Caulerpa. Does this mean that he is running out of food? <<Maybe just searching for food organisms'¦how much/what types of foods do you feed? Is my tank simply too small for this kind of fish? <<Probably'¦especially so if you don't have an appropriate substrate for this fish>> Can I keep him and start feeding him mysis or brine shrimp, or should I simply take him back to my LFS before his health declines? <<Meaty foods will be heartily accepted'¦and even New Life Spectrum pellets ( a 'very good' dietary supplement for ALL your fishes). But the issue of environment must be considered. Ideally the fish should be in a larger tank, but if you have a fine-sand substrate and can keep it fed well the fish will probably be fine (but this pretty much 'fills you up' re any more additions). Though if the purpose of the sand bed is nitrification'¦once A. phalaena starts digging in a tank this size, it can render a DSB a moot point>> Thanks so much in advance! <<Happy to share. EricR>>