Substrate heating?

[Lightning Bug]

what is the actual temperature difference between tank water and substrate? Is the purpose to have the substrate warmer than the tank water?

the purpose of snaking a heating coil through different parts of your substrate is to cause nutrients in the substrate to not be stagnate (for instance, if you use fert tabs). the heating coil doesnt not heat the entire substrate uniformly, it only heats the immediate area in which it is placed. since heat rises, the water in that area will rise and take the nutrients with it... and since that vacuum has to filled colder water from other places (adjacent to the heating coils) move in to take its place... and brings more nutrients with it... at which point the cold water gets heated up and the cycle continues so as to constantly move water and nutrients throughout your substrate. that is the purpose of using a heating coil. i do not know if it actually works in practice, but that is the theory behind it. hope that helps.

 

[plantbrain]

The problem with the theory is that diffusion occurs at the optimal rate of flow already.
Plant roots also pull in nutrients and add O2 and have a massive effect on sediments.

We cannot take an engineer attitude and approach to biological systems and ignore the plant's effect on the sediment, that is a huge knowledge/understanding gap that is involved with the entire theory behind heat cables.

The logic behind it does not even get off ground and preys on the ignorance, not data or results. If you know what redox and flow rates through the sediments are optimal for most aquatic plant growth, (say you are large commercial nursery growing aquatic plants and NEED to know such information for your business), then you can actually say something about whether or not.........such flow rates need to be increased.............or not.

The problem with cable proponents and vendors...........they lack this basic knowledge and sell based on the sugar pill "placebo test". "Looky at my pretty tank example which I attribute to heat cables!" This does NOT illustrate that the cables have any impact on plant growth, it might not do anything, but because it's a nice example of a planted tank, many assume that it is, or might be.

This is baloney.

I've been after these vendors and proponents for 15+ years and not one has ever discussed anything other than parroting the past marketing mumbo. If you ask the commercial growers, they laugh, they do not use it. If you ask for any data relating relative rates of growth of aquatic plants and redox levels in sediments, you get no response. These bozos have not even done the basic test to see if what they claim is even the least bit true.

Harsh? Deservingly so.

So do you know what the optimal flow rates are? Redox levels?
Without knowing that, aquarist really do not know and need to be much more skeptical about this.

A good flow rate is about .49liters/m^2 per day, which is the same diffusion flow rate without any thermal flow. If you add cables, it's no longer optimal, it's too high.
Redox? About 200-350Mv. Depends on the sediment type and the status and establishment of plant roots.

So tell me, have you seen or read anything from any of these vendors hocking this stuff.........about any real data, or just the illogical placebo test test?
I never have. It's not that I have not been looking either.



Regards,
Tom Barr

 

[russellah]

the purpose of snaking a heating coil through different parts of your substrate is to cause nutrients in the substrate to not be stagnate (for instance, if you use fert tabs). the heating coil doesnt not heat the entire substrate uniformly, it only heats the immediate area in which it is placed. since heat rises, the water in that area will rise and take the nutrients with it... and since that vacuum has to filled colder water from other places (adjacent to the heating coils) move in to take its place... and brings more nutrients with it... at which point the cold water gets heated up and the cycle continues so as to constantly move water and nutrients throughout your substrate. that is the purpose of using a heating coil. i do not know if it actually works in practice, but that is the theory behind it. hope that helps.

Yeah i get that it more closely mimics nature because the sunlight heats up the ground more than the water and florescent bulb doesn't do that. I just don't think i need it for my purposes. I want my plants to be healthy but don't need them to grow fast and actually the slower they grow the better probably.

 

[russellah]

The problem with the theory is that diffusion occurs at the optimal rate of flow already.
Plant roots also pull in nutrients and add O2 and have a massive effect on sediments.

We cannot take an engineer attitude and approach to biological systems and ignore the plant's effect on the sediment, that is a huge knowledge/understanding gap that is involved with the entire theory behind heat cables.

The logic behind it does not even get off ground and preys on the ignorance, not data or results. If you know what redox and flow rates through the sediments are optimal for most aquatic plant growth, (say you are large commercial nursery growing aquatic plants and NEED to know such information for your business), then you can actually say something about whether or not.........such flow rates need to be increased.............or not.

The problem with cable proponents and vendors...........they lack this basic knowledge and sell based on the sugar pill "placebo test". "Looky at my pretty tank example which I attribute to heat cables!" This does NOT illustrate that the cables have any impact on plant growth, it might not do anything, but because it's a nice example of a planted tank, many assume that it is, or might be.

This is baloney.

I've been after these vendors and proponents for 15+ years and not one has ever discussed anything other than parroting the past marketing mumbo. If you ask the commercial growers, they laugh, they do not use it. If you ask for any data relating relative rates of growth of aquatic plants and redox levels in sediments, you get no response. These bozos have not even done the basic test to see if what they claim is even the least bit true.

Harsh? Deservingly so.

So do you know what the optimal flow rates are? Redox levels?
Without knowing that, aquarist really do not know and need to be much more skeptical about this.

A good flow rate is about .49liters/m^2 per day, which is the same diffusion flow rate without any thermal flow. If you add cables, it's no longer optimal, it's too high.
Redox? About 200-350Mv. Depends on the sediment type and the status and establishment of plant roots.

So tell me, have you seen or read anything from any of these vendors hocking this stuff.........about any real data, or just the illogical placebo test test?
I never have. It's not that I have not been looking either.



Regards,
Tom Barr

Well good. I'll i know is that I won't be doing a disservice without them. thanks!

 

[wesleydnunder]

Long before I had access to the thoughts of Tom, RTR and others, I bought into the hype and set up a tank with substrate heating. The plants grew great! Hey... it works!

Baloney. At the prompting of a local long time planted tank enthusiast, I set up an identical tank without the substrate heating. You guessed it... the plants grew great.

While I don't pretend to have the scientific ability or knowledge that Tom and others possess, I can see something if my nose is rubbed in it.

Substrate heating is NOT needed. Period. I've had some beautiful planted tanks since then and none have had or needed substrate heating.

Mark

 

[Lightning Bug]

i never got one cause i didnt want my fish that bury themselves to get burned.

 

[plantbrain]

Well good. I'll i know is that I won't be doing a disservice without them. thanks!

Yep, none us will
I'm still mad at Dupla because I bought 2 of them for 500 and 700$ back in the late 1980's:duh:

did mange to sell them off a few years later for a decent $.



Regards,
tom Barr

 

[plantbrain]

i never got one cause i didnt want my fish that bury themselves to get burned.

That different in depth also changes the flow through the sediment,s thus throws off the entire theory unless you have "flat sediment syndrome", which does not look good IMO.

Digging fish also would create pockets of high flow and reduce the evenness of flow. You also have certain regions, that get detritus and clog more than others. As the detritus builds up, the pores clog and flow is restricted.

This is not a homogenous flat sediment that is the same forever.
Plant roots, detritus build up, differences in depths, bacteria, fish digging etc........

Regards,
Tom Barr

 

[RarePetFish]

Hm, the idea of substrate heating was dropped by ADA years ago. Also - if there was any real benefit from heating the substrate we as a whole would have gradually figured it out despite the inconsistent way we go about the planted tank hobby.

As long as the water flow in the tank is good the substrate will be warm enough.

That being said I do not have any personal observations if a substrate heater makes a difference. But I do know that crypts grow very well in an established tank in which the substrate is definitely cooler than the water.

--Nikolay