Fluval Bio Stratum Fish Substrate, 17.6-lb bag

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$65.99 List Price
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About This Item

Details

  • Promotes healthy plant development, growth and vibrant color.
  • Infused with nitrifying bacteria that help to break down waste and kickstart the nitrogen cycle.
  • Helps to reduce ammonia levels and stabilize water in new aquariums.
  • Lightweight granules won’t compact or restrict root growth.
  • Porous granules promote helpful bacteria growth and help to filter water.

Instructions

Frequently bought together

Questions & Answers

2 Customer Questions

Do this have to be replaced?

Do you have to wash the substrate?

Answer by Chewy • Feb 24, 2025
This substrate should be rinsed.
Reviews
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4.5
Rated 4.5 out of 5 stars
60 Ratings
Terms & Conditions

25 Customer Reviews

Rated 5 out of 5 stars
By Robert on Jan 16, 2026

Great product

I used it under my sand but some has managed to get to the top from my sand moving around and it's great, i wishful i would've used this instead of sand

I used it under my sand but some has managed to get to the top from my sand moving around and it's great, i wishful i would've used this instead of sand

Rated 5 out of 5 stars
By Weird on Oct 17, 2025

Good substrate!

Works for my 30g planted tank, plants love it I don't rinse just toss it in and let my filter and plants soak up the extra nutrients.

Works for my 30g planted tank, plants love it I don't rinse just toss it in and let my filter and plants soak up the extra nutrients.

Rated 5 out of 5 stars
By Lyndsi on Jan 19, 2026

Great price!

Love this stuff. Chewy has fo the cheapest

Love this stuff. Chewy has fo the cheapest

Rated 3 out of 5 stars
By Rose on Jun 24, 2025

Impossible to clean

Wondering what the cost of all the water I needed to rinse this out was in the end. Spent a half hour on a small bowl of it, rinse, dump, repeat. Water never stopped

Wondering what the cost of all the water I needed to rinse this out was in the end. Spent a half hour on a small bowl of it, rinse, dump, repeat. Water never stopped turning black so eventually I gave up. Tank was brown for a few days but eventually it settled. Now It will probably take a month of tank cleaning to get rid of the debris but at least my plants are happy.

Rated 2 out of 5 stars
By Briar on Jun 6, 2025

Smaller than Advertised

While the quality of the item is good, I’m very frustrated by the sizing. In the item description it is advertised to be 12 x 19 x 4.5 inches. Instead it measures

While the quality of the item is good, I’m very frustrated by the sizing. In the item description it is advertised to be 12 x 19 x 4.5 inches. Instead it measures at 10 x 19 x 3.5 inches. If you’re not going to advertise the amount in quarts/gallons/liters, at least have the sizing correct. It does weigh in as advertised. I had done the math for how much I needed and now have to order more. I will be supporting my local pet store instead.

Rated 5 out of 5 stars
By Hannah on Aug 27, 2025

Good Dirt

My plants are growing absolutely amazing!! It’s in pebble-like format so no need to cap the soil with anything if you don’t wish to!

My plants are growing absolutely amazing!! It’s in pebble-like format so no need to cap the soil with anything if you don’t wish to!

Rated 5 out of 5 stars
By Emily on Jul 24, 2025

Plant heaven

My plants started flourishing after not growing well in regular gravel. The new plants that I added are growing like crazy too. Expensive but worth it!

My plants started flourishing after not growing well in regular gravel. The new plants that I added are growing like crazy too. Expensive but worth it!

Rated 2 out of 5 stars
By Judith on Mar 17, 2025

SUBSTRATE

Man, this stuff was brutal....took hours just to rinse to where I thought it "had" to be clean.....finally got it in tank...tank water was black...I had to get up

Man, this stuff was brutal....took hours just to rinse to where I thought it "had" to be clean.....finally got it in tank...tank water was black...I had to get up four times during the night to clean filters....plus what I did before I went to bed....I was diligent in constantly cleaning filters....ok, let me see in the morning....was crystal clear!! Mazing folks.....seems to be agreeing with my plant life....keep in mind, don't disturb it...will cloud up...settles down in about an hour.....guy in fish store says he's had his for over a year...fish and plants love it....so, if you don't mind a lot of initial work...I think it will be worth it...but maybe next time...little stones!!

Rated 5 out of 5 stars
By Phylis on Aug 19, 2025

Ease of use

Easy to use work’s great for setting up a planted tank.

Easy to use work’s great for setting up a planted tank.

Rated 5 out of 5 stars
By Leanne on Jun 24, 2025

Love fluval stratum

Don’t rinse it despite what the bag says. Great substrate for live plants

Don’t rinse it despite what the bag says. Great substrate for live plants