Onyx Sand

ArkyLady

Addict In Training
Nov 27, 2002
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Arkansas
Seachem claims that Onyx Sand has "buffering capabilities". I'm assuming this means it helps raise/stabalize KH levels?

I have very low KH (around 1), so if this is really true I'm thinking Onyx Sand would be my best bet for a substrate. Plus it looks awesome. Is Onyx Sand alone suitable for a planted tank? Or will I need to mix something with it (under it)?

Thanks!
 
It works very well alone! Your situation is probably the ideal use for Onyx. :)
 
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I agree with Sumpin'fishy... You don't need anything added to Onyx for live plants. But, I do put Root Tabs down for added fertilization, and use liquid fertz too.. :)
 
Flourite, Flourite Red, Onxy Gravel and Onyx Sand are excellent substrates for planted tanks. They do not however contain required nutrients other than iron. I'm not sure how this proto-myth has arisen on the web, but Seachem makes no such claim for the products, and they certainly would if it were true, nor do experienced planted tank folk use these substrates without supplements. They are good substrates due to their structure and porosity which gives them the ability to complex many minerals , holding them for the plants easy access, but they do not come loaded with them.

They are excellent substrates, but not fertilizers. Big difference, huge.
 
I didn't mean to suggest that I thought I could just use the onyx sand and never use any fertilizer for the plants. I just wanted to make sure that the onyx sand didn't need to be mixed with something else (flourite, laterite, etc) to make it better.

In my outdoor garden I use Miracle Grow potting soil, but I mix it with humus. Even with the best soil to start with, I still use fertilizers. I'd assumed this would be the same for aquariums :)
 
You understood exactly what 80gJoe and I were saying, Arkylady. The substrate doesn't need to be mixed with anything else for excellent growth potential. Of coarse fertilizing is a separate issue, and I strongly suggest it.
 
Myth ?

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A quote from Dr. Foster Smith new catalog on page 118, "Substrates -
Start with a high quality, mineral rich gravel such as SeaChem's Flourite or Onyx Sand to lay the foundation for further success. Although a low cost gravel may save money in the short term, this will be more than offset by using more supplements to make up for the shortcomings of such gravels.
"

With that statement, is Iron the only mineral in Onyx?

This is from SeaChem's website: "Onyx Sand™ provides not only iron and other minerals but supports optimal KH levels for freshwater planted aquariums. Onyx Sand™ is most effective when used alone...."

Seems like SeaChem is claiming to have other beneficial minerals in it, not just Iron.

RTR, yes, Onyx is in no way a fertilizer, but a superior substrate.
 
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