Lost 2 Blue Dot Gobies in 36 Hours But Don't Know Why

[JohnPH]

Hi, i bought two sand sifting blue dot gobies at the weekend and added them to my tank. Both looked in fine health and were happily sifting sand during the first day. On Monday I noticed that one had disappeared and I found it on the bottom. Yesterday I discovered the other also on the bottom but I can't work out why they died. If I lost just one I would assume it was just weak or stressed but to lose both seems like it's more than just bad luck.

All water parameters are fine. I have a Seneye measuring pH, temp & Ammonia & I test nitrates weekly (currently around 3-4 ppm). Salinity is fine and all the other fish and corals in my tank look healthy.

My other tank mates are 2 clowns, a one spot fox face, sailfin tang, six line wrasse, algae blenny & a fire fish. I didn't think any of these would be a problem and I didn't witness any bullying during the time I had them.

I'd like to replace the gobies as they were great characters and useful for cleaning the sand bed but I'm a bit nervous about doing so without knowing what happened to the first two.

Can anyone suggest why this might have happened??

 

[najer]

What size tank is it?

 

[JohnPH]

It's a Red Sea Reefer 350

 

[najer]

I wouldn't try again due to at least 2 fish you have in there if the volume I just googled is correct.

 

[JohnPH]

You think the tank is too small??

 

[Haydn]

How long has the tank been set up and how deep is the sand bed.

 

[JohnPH]

Hi, tank has been running about 4 months & sand bed is around 2-3 inches. Thanks

 

[Haydn]

My guess is they were well on the way before you bought them. These fish need a mature sand bed to maintain them, if the LFS had them in a bare bottomed tank for a while they would already been starving, your sand bed is not mature enough to have the amount of life they need to survive and with the stress of the tank move they were pushed over the edge, sorry.

 

[Cell]

But you say you have a Seneye hmmm @brandon429

 

[JohnPH]

OK thanks for the info Haydn. Seems to be a plausible explanation but I was feeding them - are they not eating the stuff that falls on to the sand bed?

How long would you say I should leave it before I try again?

 

[JohnPH]

But you say you have a Seneye hmmm @brandon429

??

 

[Haydn]

OK thanks for the info Haydn. Seems to be a plausible explanation but I was feeding them - are they not eating the stuff that falls on to the sand bed?

How long would you say I should leave it before I try again?

If you look at the way they feed, taking a mouthful of sand and filtering it, they rely on enough of the right food being in the substrate. In a new tank there just isn't enough invert life in the sand to maintain them.

I wouldn't attempt these fish unless you have a big area or the tank is over a year old.