Shrimp Eating Calcium Carbonate Pebbles?

[blubird101]

Hey! So the shrimp are doing great, I now have had several berried females and lots of babies! The tank doesn't have any visible algae like some of your wonderful tanks on here, but the shrimp are always picking on the rocks and substrate, so I assume they are getting something! Plus I feed one flake of fish food a month.

Today, I noticed that two or three shrimps were fighting over a little calcium carbonate rock I bought from here. They would hold it in their hands, and swim with it and what looked like eat it...if one would drop it, another one would scoop it up and go to town. I have them just sprinkled on top of my substrate. It looks like they might have broken it into smaller pieces, as the same piece has now multiplied into two or three smaller pieces. (unless they found some really small pieces elsewhere in the tank, which is a possibility, but I don't see any pieces that small in my tank.)
Is this normal haha? Maybe a way of them just regulating their calcium intake? Lol I don't know. Thoughts? I've attached a picture.

[SuperProofer]

They may not be eating the calcium itself, but the biofilm that covers it (and everything else in the tank). My guys will occasionally pick up grains of the sand substrate and just swim around with them. Shrimp version of drive-thru??

[Dch48]

I have seen mine picking at the small piece of cuttlebone I dropped in. I think they do eat small bits of it. After all they do eat the discarded molts.

The brown slime and green spot algae on the sides of the tank are gradually decreasing. The shrimp and the little Horned Nerite are cleaning it up. I'm just a little concerned what they will have when it's gone. I mix up some Spirulina powder with water in a small cup once a week for my cherry shrimp so maybe I'll just drip a couple of drops in the Opae tank.

[blubird101]

Oh, you're probably right that they are just eating the biofilm off of it haha. Weird though that they would take it with them haha. Silly shrimp.

And hey Dch48, if you can see algae you're fine! haha. No need to feed extra. Some would even say that my feeding once a month is too much I'd just leave your tank be. If you see the opae just swimming around endlessly without really "grazing" ever, then I might worry a little more.

[Dch48]

I'm at the point now where there is no visible algae anywhere. Except for the 2 pieces of macro of course. There used to be a lot of brown and green spot everywhere. Even the slime coating that was visible on the empty Nerite shell has disappeared. Should I worry they are running out of food?

[Varanus]

If they're still happily scrubbing away then there is food. Still, if there is no visible algae then you can add a tiny bit of food as a treat every month or two.