luminescent sand

[Mebious]

Hey

New member here
Recently got interested in these little shrimps and I set up a 30L aquarium for the very first time. Who would've thought that haha.

Through these shrimps I also discovered the Marimos, those little mossballs who are also pretty interesting in itself.
I know a friend of mine always wanted to have one of those marimos, so I thought about making a bottle or a jar with a marimo in it.

So as you might've guessed from the title, I thought of adding luminescent sand to the marimo, and ofcourse, now my question:

Do you think I could add opae ula to this bottle/jar?

I've heard about luminescent rocks and pebbles, but I'm not sure if they're fish/shrimp safe?



This is the sand I'm going to use for the marimo.
( not the bottle pictured above..The bottle would obviously be too small for them haha. I just have a couple lying around where I want to take the sand out from)

Any thoughts?

[LeShrimp]

The sand glows because of Noctiluca right? If so I think it would be ok if they can survive the water conditions the opae live in. But I would wait for a response from mustafa before you do anything.

[Mustafa]

I'm pretty sure (as in 100%) that it's not Noctiluca scintillans (or any other glowing organism), LeShrimp.

@Mebious
I would be very careful with products like that. There is obviously a chemical reaction going on (i.e. something mixed into the sand) and the chemicals involved may be toxic. Plus, if I understand you correctly, you are thinking about keeping shrimp in a marimo ball setup? You realize that the marimo ball will just die at the salinities at which these shrimp live, right?

[Mebious]

Really? I did a little research before getting the marimo ball and most websites I found said that they can live in either fresh water or brakish water ( up to 1.015) (
Found the following information on wikipedia

In Lake Akan the epilithic filament form of marimo grow thickest where dense salty water from natural springs flow into the lake.

So I assumed brakish water would still be okay.

Would be really bummed if the Marimo will just die in here. Oh well, I'll see how things go and will look for something else to replace it then.

Thanks for the information on the luminescent sand. I'll still try it for a small marimo tank ( with fresh water) but won't be adding any shrimps ofcourse for their own safety

[Mustafa]

"salty water" starts at 0.5 ppt, which most freshwater plants and organisms can take without a problem. So, the salinity tolerance of Marimo balls needs to be determined. I became curious about this, too, so I went out and read a few papers...it appears like the species that forms the Marimo balls, Aegagropila linnaei, can take very low salinity brackish water. Sources seem to differ, but I've seen "under 4 ppt" and "under 6 ppt" mentioned in various papers. However, the ball form seems to always occur in freshwater. The form that grows in places like the low salinity areas of the brackish baltic sea is the type that grows like many other hair algae/filamentous algae...attached to the sides and undersides of rocks. You would not even recognize that growth form as "Marimo." So, the only thing you can do is experiment... Figure out if a Marimo ball can take somewhere between 3-6 ppt and still look healthy 3-6 months afterwards (it takes that long to figure out if the Marimo is still alive, as it can still look green for months even in high salinity water...as it's dying slowly). If so, and your tank looks established enough, you can actually add Supershrimp as long as you don't use that glowing sand. The shrimp can live just fine at those salinity levels. Just make sure to use salt made for reef aquaria and use a hydrometer, or, better, a refractometer to measure salinity.

[Mebious]

Thanks for clearing that up Mustafa

So If I put the gravity between 3-6 ppt will the shrimps still reproduce? Or maybe I'm better off getting a seperate tank if I want them to breed.

I have an empty tank right now that's at +- 0.013 right now, this is where I've put the marimo in couple weeks ago thinking it would be alright

[Mustafa]

What exactly do you mean by "0.013" Is that supposed to be salinity? If so, what units? I have bred these shrimp at 8 ppt before...don't know if they will breed at lower salinities. I guess only experience will show.

[Mebious]

woops, correct that first 0 to a 1 , specific gravity 1.013.

Guess can only try and see what works. If my marimo is still alive in half a year I'll let you know

[Mustafa]

Thanks for the correction...makes sense now. And, yes, I'd be interested to know if the Marimo ball is still around in half a year.