Sub-substrate under flourite?


Plant Guru Team
Lifetime Member
Sep 23, 2007
South Florida
Hi Tom,

I notice over time that I succumb at times to not dosing EI as reqularly as needed and I do not have a good person for when I go away for extended times....

The plants will do better with extra sources I am sure.

So, I have black flourite now (< 1 yr old) and would like to have some substrate nutrients available to my plants as well.

Can I add worm castings or such UNDER the flourite? I can do sections at a time to facilitate things and reduce risk.

The tank will remain filled (well partially anyway) during the swap as I do not want to tear down the tank completely if possible:)

Or is it better to bite the bullet and replace with a 'better' nutrient rich substrate and still do a section at a time. I dread the thought of adding ADA to a mature tank due to NH4 leaching..........

It is a mature 180 gal tank with good mech and bio filtration. Many cards and not much else but some Espei pencils.

Any suggestions are welcome.


Lifetime Charter Member
Lifetime Member
Jan 24, 2005
Sacramento, CA
I have had black Flourite sand as a top layer over both mineralized topsoil and partially mineralized river silt. Both did ok, even though this was in a 10 gallon tank with less than adequate lighting. I didn't run into lots of algae problems either time.


Lifetime Charter Member
Lifetime Member
Jul 27, 2007
New Hope, Pennsylvania
I would remove enough of the flourite to cap the substrate when done. Then add the wormcastings to your existing mixing well, and recap. You could do this in sections adding peat and osmocote to the base also if you went this route.

If done quick enough, I would imagine you could keep some of the bacteria intact. Tom I'm sure would have some ideas on how to facilitate the transition well.

Tom Barr

Staff member
Jan 23, 2005
I'd go ahead and bite the bullet, place fish in trash can for temp home, and give things 3-4weeks. I'd go with the ADA AS alone, use the chance to really scape from the ground up well.

Clean the tank out entirely.


Fish will be fine with routine water changes, filter and a heater.
Use the chance to really set the tank up the way you have wanted.

Tom Barr


Lifetime Charter Member
Lifetime Member
Nov 21, 2007
Los Angeles, CA
place fish in trash can for temp home, and give things 3-4weeks

What the hey? You can just put fish in a trash can for 3 or 4 weeks? Just hook up a filter and go? Sheesh. I've always set up a new tank when I had something to do like Gerry. That's why I have 4 tanks in my tiny room, and it is getting overcrowded. Of course, I seldom dismantle a "temp" tank, figuring it's a good opportunity to try something new. :)


Plant Guru Team
Lifetime Member
Sep 23, 2007
South Florida
Hi all,

Many thanks for the ideas/responses.

I think I will take Tom's advice and REPLACE the substrate with ADA at one time. At the same time I will try the DSM method to alleviate the nH4 issues. I have a 45gal for some of the fish and I have used 40 gal rubbermaid containers at times during moves. HOB filters work great for these containers..........

So need to house them for 4-6 weeks if DSM.

May be a bit, as that will give me a chance to redo the intake plumbing a bit and REPLACE my stand. It has a wooden floor and over the years too much water has warped it. The NC canisters sit at an angle lol

I really like the metal frames that Oliver Knott uses on large tanks. They have a removable front/sides for easy access to under the tank. And the cover can be decorated in any way. I will check these out as well.

Also I need time to plan the DSM layout. Will be some HC I think and some Anubias sections......

And.... gives me a chance to do the light suspension with the pipe bending method or something nice..........I like the way you guys have done it.......

Ted, yeah if trash cans can be used, why have a nicely decorated tank??? Oh SEE the fish LOL

Your 4 tank issue is why I have one large tank and the quarantine and that's it. When I have a house, there will be a fishroom fer sure!

Thanks again!