Beach sand + black sand

[Cruise Control]

Okay, so I went to the beach over the weekend and got some beach sand (more like beach gravel - not as fine as sand) for use in my aquarium. I've rinsed them out thoroughly and am currently drying them out in the sun.

From what I've read beach sand isn't really good for an aquarium cos the corals in the sand raises the PH level. My tanks is currently stocked with black gravel (onyx?) - it's NOT gray, it's completely black & shiny. I was thinking of mixing the beach gravel with the black sand to get a very natural looking, dark colour. What are your thoughts on doing this?

I've had this tank for about 5 months now.

Tank specs:
Black sand
Driftwood
Power filter (lined with corals & filter media)
Air wand
Lightly planted

Fish:
1 x Angel fish
1 x Ruby/Rainbow shark
1 x Bristlenose Pl*co
1 x Red Crayfish

[QCppg]

Where is this beach that you got this sand from? Volcanic and alluvial sands should be safe, however coral sand does leech out into the water.

[Cruise Control]

I got the sand from Phuket, Thailand from a beach called Kamala Beach. Not sure if it's volcanic sand or not.

[aquariumfishguy]

That is a very nice beach, indeed!


Kamala Beach
http://www.thaiways.co.th/phuket/image/beach_kamala.JPG

[happychem]

The sand itself is fine. What you need to concern yourself with are the bits of coral/shells in the sand. The easiest way to solve this problem is to get some muriatic acid (be very careful), here's a link that describes a procedure for treating the sand:

http://www.aquarticles.com/articles/plants/kumar_substrate.html

He recomends using industrial grade acid. If you're using muriatic, which is a dilute form of HCl, decrease your dilution factor.

Before you embark upon this journey, you may first just test your sand. Add a few drops of the acid to your washed sand. If it fizzes, you'll probably need to acid clean it.

The other point is, what is the pH and KH of your tank? If you've got a high KH, chances are that you needn't worry about the carbonates in the sand to begin with.

[Traci]

You might also want to reconsider the angelfish/crayfish combo. They aren't really compatible. Crayfish require unheated water, angels need a heater. THe fins on the angel would be a huge temptation for the cray as well. In general, cichlids and crays shouldn't be combined.

[Cruise Control]

Wow, hydrochloric acid! I'm not sure if I can find it over at my local hardware store but I'll check. Thanks, hapychem, for the link. It was very helpful! I'm reading more into treating substrate on the web just to get a better idea.

Yes, aquariumfishguy, it was 8 days of glorious beach for me! Absolutely brilliant!

Traci, yeah I know about that combo. Found out about AC a tad bit too late, though and the experts here informed me about them in a seperate post. I'm getting rid of my angel this weekend to a LFS :( It's sad, though, he's a real beauty with very pretty finnage. It's funny, but I haven't seen any problems between the cray and angel at all. They just seem to mind their own business but I suppose it's just a matter of time.

Thank again, guys/gals. AC does it once again for me!