How do I feed these fish while I’m away?
I have a 45cm cube reef tank, set up about nine months. It has a nano skimmer and live rock filtration and I also use carbon and a Polyfilter. It is home to two Yellow coral gobies, plus a hermit crab and another very small stowaway crab I see from time to time. The tank contains Xenia and mushrooms.
I’m going on holiday for 10 days in the autumn and I have no one to feed the fish. They won’t touch any of the dried foods I’ve tried, so an auto feeder is out of the question. A shop about 20 miles up the road sells live rotifers in bags. If I buy a couple of bags of these and add them before I go away, will they last long enough for these fish to be OK?
I don’t want to trust a neighbour as I had a bad experience in the past with a tropical tank being badly overfed and this is such a small set-up that I would sooner not risk it.
SI NICHOLLS, EMAIL
DAVE SAYS: Your corals and crab will be fine for 10 days with no additional feeding, so I wouldn’t be concerned about them. However, this is definitely going to be pushing it for the gobies, so you’re right to be concerned about them. These little fish will start to starve after a few days of not feeding, and they lose condition rapidly. The tank should provide some natural zooplankton that they’ll eat without supplementary feeding, but almost certainly not enough to justify leaving them for more than five days without additional food.
Blitzing the tank with live food before you go away is a good idea, and will probably be sufficient for four or five days (obviously depending on how much you add). Adding live rotifers would help in some way as any copepods present can use these as a food source. Live rotifers are very small indeed, however, so you’ll want something larger as food for the gobies. Copepod cultures will be the best bet as they’re much larger than rotifers, so speak to your local fish shop and ask if they can sort you out with some – ideally, both Tigriopus (‘Tiger pods’) and Tisbe; of these, Tigriopus are slightly larger.
You might want to start adding copepods a week or two before going away to make sure you’re happy with the amounts and to get the system really seeded with them. Add them to the tank just before going away for sure, but I think it’s best to ask a trusted neighbour to check on the fish and add a further shot or two of copepods around day five or six. Copepods will survive for a long time if kept in the fridge – label up what you want your designated fish-sitter to add, and ask them to remove it from the fridge about half an hour before feeding and float the bags or bottles in the tank (this will help to prevent the copepods becoming shocked). They can then simply tip the contents into the tank. I don’t think you’ll have any problems with the tank being overfed in this way.
It’s probably a good idea to also leave the number of your local fish shop with the neighbour if anything does need sorting while you’re away – just in case. I hope this helps. Have a good holiday!
Building up stocks of live foods is the way to keep these gobies fed.