Re-setup substrate questions

Hi Tom,

I'm planning to re-setup my 175 gallon planted tank and I'm wondering if I should reuse the old substrate or chuck it out. By re-setup, I mean remove everything in the tank and rescape etc.

This tank is using pond soil and has serve well for the last 2+ years. If I understand your non-CO2 method article correctly (I'll be using CO2 for this tank), I know that the soil probably ran out nutrients some 18 months ago. So should I keep this soil, or replace it?

My reasoning for keep the soil is that it has served well, the plants are healthy and if I don't redo the tank, it'll still be there anyway.

My reasoning for replacing it with new soil is to give the new setup a fresh start. It'll be a number of years before I re-do the tank again.

I do understand that once a substrate has given up it's nutrients, the tank can still go on with no problems if the plants can get it's needs from dosing the water. So I guess I just want to get your thoughts/opinions on this.

I haven't gotten NH4/Urea problems with this soil, and I've been using it for a few tanks. The packaging says it's specially prepared for pond usage and has little or zero amounts of NH4/Urea, NO3 etc.

Next question... you suggest Flourite/Onyx sand for non-CO2 tanks for the Mg, Ca and other stuff. I guess I can use it for a CO2 tank too (right?), but it's expensive to top a 175G tank with that stuff. Will a bag suffice? I'll be potting a Nuphar japonica to stop it from roaming my tank over the next few years, and I can just top that pot with Onyx sand. The pot will be easily removable, so, I can refresh the Onyx anytime.

Lastly, I'll be keeping the old gravel and going to re-use some of it (unwashed) as a layer (0.5 to 1 inch thick?) between the soil below and a fresh clean layer of gravel on top. There should be enough mulm in there to kick start the substrate, right?

Thanks.

 

Re: Re-setup substrate questions

It's J. Arthur Bower's Aquatic Compost. It's basically potting soil for use in ponds.

I have a smaller 50G tank due for a re-vamp too... I'll consider all Onyx sand for that one. This is the tank for the arowana and so I can't go smaller.

It's only US$12 a bag for you guys? They go for S$35 a bag here (Singapore). S$600 is way too much for me.

I was still planning on using the soil (new, just decided) on the bottom, about an inch thick topped with half an inch of the old unwashed gravel and then either an inch of clean "normal gravel" or Onyx sand on top.

Onyx and the old gravel sounds like trouble to me... once they start mixing from planting and uprooting.

I'll probably go with just gravel and the pond soil. It's worked for me and I'll have to stick to that for now, but I'ld like to hear your thoughts on how that'll compare to an all Onyx sand substrate. And why you prefer an all Onyx sand substrate.

The existing setup is already low maintenance and I've planned the new setup to be as well. I know 3WPG doesn't apply to tanks this size. I'm acutely aware of circulation and CO2 distribution problems.

All the same, I'll love to hear some of those suggestions.

 

Re: Re-setup substrate questions

Sorry for continuing this off topic post...

A lot of the plants in Oriental Aquariums are not directly available to locals. They grow plants mainly for other companies, like Tropica and the are not allowed to sell the plants locally, but only to export them out to their clients. So some cultivars especially patented ones... have to make a trip to Europe, where they get branded adn then sent back to Singapore and get sold at exhorbitant prices.

But no one buys Tropica here, for common plants. Only the newer, more difficult or rarer cultivars. Few do that too, since common plants cost only a few dollars a pot. Most plants are available thru LFS, or direct, from the farms here or the importers/exporters who get their supply from places like Thailand and Malaysia.