Substrate Advice

harveys_harvest

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I recently picked up a 32-gallon BioCube setup, and along with the tank and filtration equipment, I was given about 5 gallons of substrate. It’s a roughly 50/50 mix of crushed coral and CaribSea sand.

I’ve been digging into it, but I’m finding pretty mixed opinions on whether this type of substrate blend is actually a good idea for a reef tank. Some people say it helps with stability and flow, while others warn about detritus buildup and long-term maintenance issues.

My plan is to keep a mix of fish, inverts, and corals, so I’m trying to set things up in a way that’s going to be stable.

Would you recommend:

- Using the mix as-is
- Modifying it (like adding more sand or removing some crushed coral)
- Or just scrapping it and starting fresh with a different substrate?

Appreciate any advice or experiences with similar setups!
 

slingfox

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Sole people like the pure crushed coral substrate, particularly if you like to crank up the flow. Others like sand since it looks great (the best look IMHO) and can provide habitats for certain types of fish including wrasse and sand sifters. Others prefer bare bottom but that is not recommended for beginners. I have not seen anyone use a mix of crushed coral and sand though. I would pick one or the other.
 

exnisstech

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I would just start new. Cleaning old sand is a hassle and it won't take a lot for a tank that size. I'm also fan of aragonite and special grade as mentioned but I haven't really used anything else except Fiji pink and it blew all over.
PS. Bare bottom is also an option and how I run 3 of my 4 tanks but it depends on whether you want to keep fish that need sand like some gobies and wrasses.
 

MegabiteOG

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I agree with the above on just changing it out. Special Grade is a great sand to use and have used it on all my tanks. My current tank I went 50/50 with dry special grade and live sand from Gulf Live Rock which is essentially crushed coral/ rubble.

I've never been a fan of crushed coral but it has really grown on me as there's a very natural look to it when mixed 50/50 with sand. I love the texture it provides and the color with all the Coralline on it. Of course, looks are subjective. Good luck with the choice!

Here's how it looks in my tank.
IMG_7932.jpg
 
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harveys_harvest

harveys_harvest

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I agree with the above on just changing it out. Special Grade is a great sand to use and have used it on all my tanks. My current tank I went 50/50 with dry special grade and live sand from Gulf Live Rock which is essentially crushed coral/ rubble.

I've never been a fan of crushed coral but it has really grown on me as there's a very natural look to it when mixed 50/50 with sand. I love the texture it provides and the color with all the Coralline on it. Of course, looks are subjective. Good luck with the choice!

Here's how it looks in my tank.
IMG_7932.jpg
Woah that's absolutely stunning! I changed it out for a sand mix! That looks so amazing!
 

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