Removing / changing substrate?

[Fluff]

Anyone have any experience with changing their substrate?

I have a fully cycled and fully stocked 1 year old 46g tank, with
plants. Originally when I set it up, the substrate was a mix of 1/2
fluorite, 1/2 resin-coated aquarium gravel. It was stupid for me to
mix in the aqua-gravel, but I didn't know better at the time.

I want to start replacing the original substrate- basically to get rid
of the fake-gravel. Anyone ever do this? Any tips?

What I plan to do is remove 4 cups of substrate and replace it with 4
cups of new fluorite that has been cleaned and soaked with tank water.
Is it Ok to do this on a regular, but methodical, basis? My plan
would be to do this twice per week. My goal is to remove most of the
fake-gravel, and if it takes months, so be it. I figure 4 cups at a
time won't screw too much with the bio-filtration living in my
substrate?

Will this idea work? It's a 46g tank, and I do change out 10 gallons
every week. PH is a steady 8, good KH, no ammonia or nitrites;
nitrates are less than 20, and I am running a well-established Fluval
304.

Am I taking any risks by attempting this?

[NetMax]

"Fluff" > wrote in message
...
> Anyone have any experience with changing their substrate?
>
> I have a fully cycled and fully stocked 1 year old 46g tank, with
> plants. Originally when I set it up, the substrate was a mix of 1/2
> fluorite, 1/2 resin-coated aquarium gravel. It was stupid for me to
> mix in the aqua-gravel, but I didn't know better at the time.
>
> I want to start replacing the original substrate- basically to get rid
> of the fake-gravel. Anyone ever do this? Any tips?
>
> What I plan to do is remove 4 cups of substrate and replace it with 4
> cups of new fluorite that has been cleaned and soaked with tank water.
> Is it Ok to do this on a regular, but methodical, basis? My plan
> would be to do this twice per week. My goal is to remove most of the
> fake-gravel, and if it takes months, so be it. I figure 4 cups at a
> time won't screw too much with the bio-filtration living in my
> substrate?
>
> Will this idea work? It's a 46g tank, and I do change out 10 gallons
> every week. PH is a steady 8, good KH, no ammonia or nitrites;
> nitrates are less than 20, and I am running a well-established Fluval
> 304.
>
> Am I taking any risks by attempting this?

Assuming you want to keep the fish inside and everything running, then
you can do it in a few passes. I siphon the substrate out using a thick
hose. Find the right diameter which will lift the substrate and not
vacuum the fish and all the water too quickly. For tanks with no fish or
big fish, I've used a 3" hose (with a garden hose re-filling the tank as
I go along). I could remove all the substrate out of a 4 foot tank in
about 2 hours. For home use with buckets, I'd go with something smaller,
like a 1" or 1-1/4" diameter hose, and do the tank in smaller portions,
with a couple of days in-between lifts.

If you clean your filter, skip a few days before removing more substrate
to ensure the bacterial balance is back in place again. AFAIK, the
nitrifying bacteria in your filter is more important and slower growing
than the bacteria in your substrate.
--
www.NetMax.tk

[Fluff]

>Assuming you want to keep the fish inside and everything running, then

Yes, I plan on keeping the fish inside during the process. I didn't
plan on using a siphon to suck out the gravel, I was going to just
scoop out a few cupfuls of substrate at a time, and then add washed
fluorite back into the tank. Maybe I'll change plans and use a
siphon... I'll probably run my diatom filter during the process to
help clear the inevitable "fluorite dirt" from clouding things up too
much, and will keep an eye out for any spikes in water chemistry.

Thanks for your response, I feel more confident hearing that you've
done it successfully.

>If you clean your filter, skip a few days before removing more substrate
>to ensure the bacterial balance is back in place again. AFAIK, the
>nitrifying bacteria in your filter is more important and slower growing
>than the bacteria in your substrate.

[Steve]

NetMax wrote:
> "Fluff" > wrote in message
> ...
>
>>Anyone have any experience with changing their substrate?
>>
>>I have a fully cycled and fully stocked 1 year old 46g tank, with
>>plants. Originally when I set it up, the substrate was a mix of 1/2
>>fluorite, 1/2 resin-coated aquarium gravel. It was stupid for me to
>>mix in the aqua-gravel, but I didn't know better at the time.
>>
>>I want to start replacing the original substrate- basically to get rid
>>of the fake-gravel. Anyone ever do this? Any tips?
>>
>>What I plan to do is remove 4 cups of substrate and replace it with 4
>>cups of new fluorite that has been cleaned and soaked with tank water.
>>Is it Ok to do this on a regular, but methodical, basis? My plan
>>would be to do this twice per week. My goal is to remove most of the
>>fake-gravel, and if it takes months, so be it. I figure 4 cups at a
>>time won't screw too much with the bio-filtration living in my
>>substrate?
>>
>>Will this idea work? It's a 46g tank, and I do change out 10 gallons
>>every week. PH is a steady 8, good KH, no ammonia or nitrites;
>>nitrates are less than 20, and I am running a well-established Fluval
>>304.
>>
>>Am I taking any risks by attempting this?
>
>
> Assuming you want to keep the fish inside and everything running, then
> you can do it in a few passes. I siphon the substrate out using a thick
> hose. Find the right diameter which will lift the substrate and not
> vacuum the fish and all the water too quickly. For tanks with no fish or
> big fish, I've used a 3" hose (with a garden hose re-filling the tank as
> I go along). I could remove all the substrate out of a 4 foot tank in
> about 2 hours. For home use with buckets, I'd go with something smaller,
> like a 1" or 1-1/4" diameter hose, and do the tank in smaller portions,
> with a couple of days in-between lifts.
>
> If you clean your filter, skip a few days before removing more substrate
> to ensure the bacterial balance is back in place again. AFAIK, the
> nitrifying bacteria in your filter is more important and slower growing
> than the bacteria in your substrate.

I've completely replaced the substrate of my 90 gal plant tank several
times over the last ten years, most recently in a change-over to
"complete substrate" in April. No problems ever resulted, but I've made
sure the filters stay "live". The whole change-over takes 4-6 hours,
which the fish and plants spend in various picnic coolers and other
containers. Most of the water is also changed in this process.
Steve