hydor hydrokable

[smit1260]

I would like to use a hydor hydrokable in the bottom of my refugium, in the hopes that the heated substrate would provide for faster macro algae growth and possibly faster anerobic activity. There would be a 4 inch sand bed on top of it. What I am wondering is if the heat would create enough current to prevent the oxygen free areas needed for the removal of nitrate?

Also can I rely on the hyrokable to heat the water in the refugium and thus the tank? or will I need another heater. It is a 30 Gallon tank with a 5 gallon refugium.

Can I use a neptune controller for the cable or do I need the hydor thremostat?

One possible solution if these ideas are a problem is putting the cable near the top of the sand bed to prevent circulation within the sand bed and increase contact with water.

 

[Anonymous]

Don't know if there is any benefit for reefs, but for freshwater planted tank, some people have good experience with it.

 

[smit1260]

Thanks -ck-,
Ya I understand the benefits for a freshwater planted tank. I just don't know the dynamics of a deep sand bed. It seems to me that many of us don't understand the technical aspects of how deep sand beds work. Maybe if we did then the deep sand bed vs. bare bottom debate could get more heated and inform us all!!!!!

I am thinking that a cable heater will increase circulation which would be bad for the deep sea bed.

Further thought and comments would be great

Dave

 

[Anonymous]

Did not really think about it, but at first glance, it does not seem to me that heated substrate will increase the circulation. There is no obvious ramifications other than your water heater need to be turn on as often, and maybe a region where bacteria won't grow as well due to excessive heat. How hot does these heating cable get anyway? If I guess correctly, it is not that hot since it should not kill FW plant's root, right?

So at first glance, it does not affect macroalgae growth (marine algea does not have vascular root like most FW plant), it does not speed up anerobic rate (depends on how hot it get, but it can be a lot more complex than just temperature since perculation and other dynamic parameters can be as important), it does not make the sand to get more oxygen (substrate in reef is a lot finer than gravels used in FW tanks), and so it does not affect nitrate rate.

Let me know if anybody disagree with my opinion.

 

[smit1260]

-ck-

I see your point about the finer sand beds not allowing circulation and not effecting the anerobic conditions. However, most biological and chemical reactions occur faster at higher temperatures. I would assume this would increase the anerobic nitrate reduction rate as long as it doesn't decrease the anerobic conditions in the deep bed or get too hot and kill bacteria. Also the increased heat would provide for less oxygen available in the sand bed.

My sand bed will be 24" x 5" X 5" and I will have 100 watts of heat entering in this area and hopefully heat my entire tank. The hydrokable is 33 ft. long so I am hoping it really distributes the heat.

I am hoping this will create heat radiating to the macro algae growing just above the sand bed.

 

[Anonymous]

Most biological reaction has an optimal temperature, and it is very sensitive to any change from it. Bacteria has a wider tolerance than, say, mammal. How do you feel when you have a fever?

The amount of oxygen in the sand will be affected very little by the sand temperature. Circulation at the boundary layer (near the sand surface) plays a larger role, for example.

Heat the sand will not make your macro algae grow any faster. But if controll well, I don't see if heating the sand will hurt anything.

 

[rayman]

i dont see much of a benefit. a dsb is what 3- 4" deep and unless you where using that as the only heat for your tank there would not be enought heat generated to create a current change, BUT with the higher temp you may get bristel works and what have you tunnling deeper and that may or may not be beneficial depending on who you ask