refuge in killifish tanks

[gacp]

I've been wondering about the use of a refugium in killies tank. The idea is to provide a secluded place where invertebrates can breed protected from the predation by the fish while trickling back in small number back to the main part of the tank, where they will be eaten. My raw idea is to use the space behind a Hamburger Mattenfilter. I think that enclosed area will be rich in nutrients and even particulate food, and could support productive colonies of crustaceans such as Cyclops or Asellus.

The tank as seen from above:


It is a terrible rendering, but I think you'll identify the Mattenfilter and the space behind it.

So, what do you think?

[RonWill]

So, what do you think?

Workable idea. Better if you're using strictly air-lift that sends the water back into the main water column.

Mine is power-head lift that pumps water to a Henri filter, through a wad of filter wool, then trickle back. I have cherry shrimps behind the MF and the shrimplets are tiny enough to crawl through the sponge but chance of them getting sucked into the pump is very possible (even though I don't think the shrimps are that dumb).

I was previously running something similar in a recirculating setup.

[gacp]

So, what do you think?

Workable idea. Better if you're using strictly air-lift that sends the water back into the main water column.

Mine is power-head lift that pumps water to a Henri filter, through a wad of filter wool, then trickle back. I have cherry shrimps behind the MF and the shrimplets are tiny enough to crawl through the sponge but chance of them getting sucked into the pump is very possible (even though I don't think the shrimps are that dumb).

Yes, I was thinking of airlift tubes only. The focus is Austrolebias spp. and they just hate water current.

Henri filter == DeBruyn filter?

I love shrimps. I keep the local poor man variety, Palaemonetes argentinus, a kind of glass shrimp, in most of my tanks. Cute, in their own way, and cheap---I get them as live food for 1 euro the couple of hundreds or so. Haven't bred them yet: they do not requiere saltwater, but they do have an abbreviated development but still have nauplius larva et al. And... shrimps are not very dumb... but accidents do happen Airlift is quite gentle.

Thanks for the feedback.

[RonWill]

Henri filter == DeBruyn filter?

Yes. We've discussed about this wet-dry filter so often, I reckon everyone would know about it already.

For the air-lift, I realized that a larger diameter tube is inefficient and needs alot of air to drive water back to the main water column. Opt for a narrower inner-diameter 1~1.5cm tube and custom bend, if needed, to a gentle inverted 'L' shape (not 'J'). That way, the returning flow is more gentle and consistant.

Gustavo, I think you already realized that the MF works much better if you seal up the sides; meaning all incoming flow is through the sponge. The bottom of the sponge need not be sealed if your gravel/substrate overlaps it by about an inch. It does take a while for the bio to establish but once it does, there's no major maintenance.

Whatever available shrimps that are easy to maintain and breed, will serve the purpose, so long as they don't have menacing pincers!

Update us when you have the refugium installed. Have fun.