Using sponge foam as substrate base

[TheBic]

Hello, and please excuse me for any errors, I am using translation software.
If I am in the wrong room, please show me the door~

In their Wiki, Aquasabi demonstrate substrate building using polystyrene plates.
I'm curious if anyone has, tried or an opinion on using 2 or 3 cm thick foam sponge instead.

I am not planning on using huge, heavy rocks and the styrene I have found so far for sale is used in the construction industry so is flame treated.
I want to use the foam as a sort of skeleton, to form the contours before adding rocks, sand and soil. (Soil is rather expensive here)
Basically, following the above Wiki - just substituting foam.

It is a 60 litre tank, am aiming for heavy planting with shrimp and 8 or so small fish.
I have a HOB filter but am aiming for as close to self regulating as possible.
Which is why I wondered if the foam base would be any advantage in filtration, cleanliness and tank health.

Looking forward to any feedback, ideas, suggestion or actual experience using foam in the tank other than as a filter.
Cheers
TheBic

 

[Matz]

Hi TheBic (any Name to takl with you would be very nice and is state of the art here ),
using the normal Styrofoam for "building" a skeleton should have no bad effect on your water-conditions.
But it gets driven-up lightly! If using much of that you have to glue it to/at the tank, or find another way to stabilise everything.
Why not using wood for that?
If using styrofoam you can cover it with epoxy-resin if you like.
Greets,

 

[TheBic]

Hello Matz, thanks for your reply - you are quick.
You are correct, using Styrofoam is easy, but it is difficult to buy untreated here.
What I really wanted was to float the idea (pun intended) of using sponge foam (or sponge rubber - the type used in filters) to REPLACE the stryo plates.
I can't see it having any negative effects, just wondering if there is any advantage to be gained in regards to improving water quality.
Wondering what others opinion was, has anyone tried it?
Both sponge and styro are easy to cut and shape - wood hmmm, maybe more difficult and not sure of it in a tank of water!

Cheers
TheBic

 

[Zer0Fame]

Hi all,

as far as I understood he doesn't want to use Styrofoam, but normal filter sponges, kitchen sponges or similar, since it's easier to acquire and the polystrene he could get has been treated.

Not sure how that would affect the biology in your tank. The general consensus here is "as little filter media as necessary", at least in planted tanks. Pretty sure it would add to filter capabilities in your tank...but might be worth a try!
Just keep in mind you might need to adapt your fertilizing routine ... sponges deep in the ground sound like they might be capable of denitrification.

 

[TheBic]

Hi all,

as far as I understood he doesn't want to use Styrofoam, but normal filter sponges, kitchen sponges or similar, since it's easier to acquire and the polystrene he could get has been treated.

Not sure how that would affect the biology in your tank. The general consensus here is "as little filter media as necessary", at least in planted tanks. Pretty sure it would add to filter capabilities in your tank...but might be worth a try!
Just keep in mind you might need to adapt your fertilizing routine ... sponges deep in the ground sound like they might be capable of

Hello, thanks for helping clarify my post.
You are correct.
Valuable feedback, interested in the "as little filter media as possible" comment.
That was sort of where I was coming from, trying to mimic nature if you will by having sponge filtering "in the earth" so to speak rather than a HOB.
Something less intrusive?
For a 60 litre tank, with a few fish, an external filter is a bit overkill I feel.
Denitrification - I need to look that up.
Can you elaborate, just a little please?
Not to complex - I am still feeling my way.
This is my last post for today - almost time for dinner then sleep.
Thx everyone.
B
p/ s I should clarify.
I mean, I thought denitrification in the tank was a good thing?
That was what I was hoping.
But your comment tends to suggest it may not be such a good thing?
So, now I'm confused~
Cheers and goodnight
B

 

[ernesto]

he doesn't want to use Styrofoam, but normal filter sponges, kitchen sponges or similar, since it's easier to acquire and the polystrene he could get has been treated.
Not sure how that would affect the biology in your tank.

wouldnt it be the same effects like using piles of lava gravel as substructure, except sponge is "elastic"?

 

[Zer0Fame]

Hiya,

Can you elaborate, just a little please?

In simple words, in a planted tank you want eliminate everything that might mess with your fertilizers.
You have probaly heard of nitrification, the bacteria that transform your ammonia to nitrites and your nitrites to nitrates?
Denitrification is the opposite of that, it basically takes your nitrates away. It happens in anaerob environments and a sponge buried under substrate should well be able to build this environment.

Denitrification can be a good thing in lightly planted, fish heavy tanks. However, in heavily planted tanks as we have, you want to be in full control of your water parameters without anything messing with them. At least for the macro and micro nutrients.

This is one of the reasons @nik from this forum here came up with the concept of "Geringfilterung". A direct translation would be "low filtration". However, don't be fooled by the name, the concept basically states that as much tank biology as possible should be handled by the tank itself and not by any filters or filter media. In short: As little filter media as possible, as much as necessary. Not only does this concept ensure that your filter doesn't mess with any parameters, but having the biology in the tank rather than the filter gives you an additional edge over algae. Furthermore it adds to the stability of the tank. Additional filter media is only added, if you see the organic load being too high, as in nitrites or unclean water. This goes as far as only having a powerhead in your tank, no filter at all. It all depends on your tank.

Hope that was understandable, if you have any questions, feel free to ask.

wouldnt it be the same effects like using piles of lava gravel as substructure, except sponge is "elastic"?

Not quite comparable I would say, as a sponge has a whole lot more surface area than the lava, plus it's more prone to anaerob zones. Lava still allows some water circulation and flow inbetween, while a sponge would slow down the flow to a minimum. The longer the same water stays in a sponge, the more oxygen is used, the more anaerob surface you have. That's one of the reasons why filters made for denitrification have an extremely slow water flow ... sometimes as low as 2 liters per hour, depending on the size. For maximum efficiency and if I recall correctly, the water is supposed to be in the filter for about 15 minutes before it returns to the tank. If you go too low though, you'll end up with hydrogen sulfide, not something you want, for the smell and toxicity alone.

 

[TheBic]

wouldnt it be the same effects like using piles of lava gravel as substructure, except sponge is "elastic"?

Thanks @ernesto , sponge is also, from my position, cheaper too. Imported soil is quite expensive, although I guess the local copy is probably as good.
But your question helped clarify another point, well, the reply did, but thanks for starting the train up.

 

[TheBic]

That was brilliant @Zer0Fame, now I see I had my head on backwards.
Everything I have read suggests one needs to eliminate nitrites if possible.
Although I had never heard of @nik's term, as I hinted in my previous reply, that was something close to what I wanted to achieve.
A more hands off approach to filtration.

I am not sure what constitutes a fish heavy tank in 60 litres, but yes, I was coming from an animal first approach thinking the nutrients in the soil would support the plants. At least for a year or two.
Again, from a price perspective fish etc cost more than plants.
Plus I don't want to "experiment" at the expense of fish lives.
I already have enough pumice, lava chips/ (reddish) volcanic rock for 3 layers each circa 1cm thick, (red rock chips slightly larger) plus sand for moulding or contouring.
Sans sand, soil and top black sand I am guessing a substrate base of around 6cm, although I expect the sponge to compress a bit under the weight.

Lightly, heavily planted is a bit subjective I s'pose, so again, to clarify, I am not aiming for a jungle, and I do intend to use more rocks in the flatter 2/3.
Perhaps the Japanese Iwagumi, with less focus on rocks, and more planted areas.
After all I only have a 60 litre tank, so I was focused on small leaved plants, small fish to create a faux spacious look.
If it's relevant to this discussion, my H20 has a Ph of 8. (litmus paper test)
I had planned to leave the finished sculpted tank for a month before planting, then check the Ph again which would guide me to best plant and stock to install.

Sorry for a long piece, thought I would try to explain as much detail to make it clearer for anyone who wants to follow on.
Thanks again @Zer0Fame , extremely helpful and useful comments.

I'm summarising them a sponge base would be great for livestock but maybe not so for plants without ongoing ferts etc?
Cheers
B

​

 

[Sentroshi]

That was brilliant @Zer0Fame, now I see I had my head on backwards.
Everything I have read suggests one needs to eliminate nitrites if possible.
Although I had never heard of @nik's term, as I hinted in my previous reply, that was something close to what I wanted to achieve.
A more hands off approach to filtration.

I am not sure what constitutes a fish heavy tank in 60 litres, but yes, I was coming from an animal first approach thinking the nutrients in the soil would support the plants. At least for a year or two.
Again, from a price perspective fish etc cost more than plants.
Plus I don't want to "experiment" at the expense of fish lives.
I already have enough pumice, lava chips/ (reddish) volcanic rock for 3 layers each circa 1cm thick, (red rock chips slightly larger) plus sand for moulding or contouring.
Sans sand, soil and top black sand I am guessing a substrate base of around 6cm, although I expect the sponge to compress a bit under the weight.

Lightly, heavily planted is a bit subjective I s'pose, so again, to clarify, I am not aiming for a jungle, and I do intend to use more rocks in the flatter 2/3.
Perhaps the Japanese Iwagumi, with less focus on rocks, and more planted areas.
After all I only have a 60 litre tank, so I was focused on small leaved plants, small fish to create a faux spacious look.
If it's relevant to this discussion, my H20 has a Ph of 8. (litmus paper test)
I had planned to leave the finished sculpted tank for a month before planting, then check the Ph again which would guide me to best plant and stock to install.

Sorry for a long piece, thought I would try to explain as much detail to make it clearer for anyone who wants to follow on.
Thanks again @Zer0Fame , extremely helpful and useful comments.

I'm summarising them a sponge base would be great for livestock but maybe not so for plants without ongoing ferts etc?
Cheers
B

​

Good Morning B,

in one sentence: A sponge would result in less control about the nutrients in your aquatic world.
The follow up problems could be: 1) Unbalanced nutrients, that leads to unwanted aglae / bacteria.

Mostly you want nutrients (CO2 also) - Plants - Light - Bacteria in a good symbotic and functional ecosystem, so your tank stays clean and healthy. And thats is way easier to maintain, if you just have to adapt on the processes in your water. If you add more filtration than necessary: More stuff to care about. If you add Sponge: even more stuff to care. As a result; ofcourse it could work (!) but if not: It is hard to find the solutions to the problems.

Greetings
Stefan

 

[TheBic]

thx @Sentroshi, and good morning.
I certainly am in favour of less stuff to care about~
I guess I am trying to find a balance between animal, plant and aesthetics without "too much stuff to care about."
So, can I summarise by saying you would go with the polystyrene, not foam sheet?
Cheers
B

 

[Zer0Fame]

Hiya,

Everything I have read suggests one needs to eliminate nitrites if possible.

oh that is absolutely correct. You definitely want to eliminate nitrites. What you do not want to mess with is nitrates!
One letter with a huge impact ... nitrites kill your fish, nitrates feed your plants.

At least for a year or two.

That depends on what water you use, especially water with a high KH (carbonate hardness) will drain your soil like crazy.

Plus I don't want to "experiment" at the expense of fish lives.

Kudos, just the right mindset.

Lightly, heavily planted is a bit subjective I s'pose, so again, to clarify, I am not aiming for a jungle, and I do intend to use more rocks in the flatter 2/3.
Perhaps the Japanese Iwagumi, with less focus on rocks, and more planted areas

With a lightly or medium planted tank and soil you might want to look into what's called PMDD or Lean Dosing. Works pretty good with soil, needs some attention to detail though, as in you need to find just the right amount.

 

[TheBic]

I'm beginning to think plastic rocks, plants and fish an easier route~

 

[Zer0Fame]

Heya,

sounds more complicated than it really is!

 

[TheBic]

Seriously though, I to do understand the basic decomposition process.
Nitrites to nitrates.
Although I can't recall seeing it explicitly written, it seem implied that filters convert or help to, nitrites to nitrates, which need water changes to remove.
My aim in going for a more heavily planted tank was based on my (possibly flawed now) thinking that a good base of flora would also eat up the nitrates, a win for the fauna. The same thinking inspired my thoughts around a foam based substrate would be an extra arrow in the nitrite to nitrate quiver. Nitrites being fatal to fish.
Ahh well, time for a rethink.
Cheers
B