Heater below co2 defuser. Is this ok?

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kashif314

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I have a small tank but without lid and my AC is directly where the tank is so I need a bigger heater than suggested per gallon. I have two questions.

1) I changed heater position from back to the side of tank where it look least bad. But co2 defuser is just above it. I want to know if this is ok or will it have any effect on co2 saturation in water.

2) Defuser was at same place but in middle before but now its near surface so is this ok also?

Please have a look:

https://youtu.be/iddKvjdyRPo

Please advise. Thanks
 
I don't see the heater hurting anything but you want your diffuser closer to the bottom of the tank to allow the co2 bubbles a longer time to diffuse. That close to the surface you are gassing off probably 90% or more of the co2 in less than a second. Do you use a drop checker? I always try to place my diffuser in the current or into the intake of the filter. Nice tank by the way.
 
To add to the above post, placing the diffuser so that the filter current pushes the bubbles around is beneficial as well. Increases the dwell time for the bubbles for better gas absorption.
 
I agree, you are wasting a lot of CO2 by having it that close to the surface / having bubbles off gas.

Place it lower in the tank and in a high flow area to distribute the bubbles everywhere and increase the contact time with the water.
 
I too concur with the placement of the diffuser. The goal is to put that as deep as possible and in a place that keeps the bubbles pushed down into the water column.

The longer the CO2 bubbles are churned around in the water column the more CO2 is dissolving into the water as carbonic acid and the more carbonic acid means more carbon for your plants. (This is also why your PH drops with CO2 addition, carbonic acid lowers PH).

This is also a reason to upgrade to a CO2 reactor to get more churn and more dissolve
 
This is also a reason to upgrade to a CO2 reactor to get more churn and more dissolve

Only to a point. A single diffuser can provide enough for a large tank (180 gallons) it just needs to be placed in the right spot to maximize efficiency.

Also, direct CO2 bubbles toughing leaves is the single best way for plants to utilize the CO2.

So the argument can go both ways ;)
 
Only to a point. A single diffuser can provide enough for a large tank (180 gallons) it just needs to be placed in the right spot to maximize efficiency.

Also, direct CO2 bubbles toughing leaves is the single best way for plants to utilize the CO2.

So the argument can go both ways ;)


yes it can.. A reactor is more efficient overall and more reliable IMO.. I've had issues with diffusers... getting plugged or watching bubbles drift to the surface and end up in the air.

As for CO2 directly on leafs. If your diffuser is distributing CO2 bubbles thoroughly to the underside of leafs across an entire aquascape then yes, but IMO in the name of efficiency and predictability I do recommend reactors and dissolving CO2 into the water column.
 
yes it can.. A reactor is more efficient overall and more reliable IMO.. I've had issues with diffusers... getting plugged or watching bubbles drift to the surface and end up in the air.

As for CO2 directly on leafs. If your diffuser is distributing CO2 bubbles thoroughly to the underside of leafs across an entire aquascape then yes, but IMO in the name of efficiency and predictability I do recommend reactors and dissolving CO2 into the water column.

Exactly the reasons I run a reactor and not a diffuser ;)

Well, I have a low pressure regulator so diffusers literally don't work with my setups, instead I run low pressure into an inline reactor.

I just wanted to make sure OP knows that diffusers will work without issue on larger tanks, and have certain benefits that reactors cannot achieve.
 
I don't see the heater hurting anything but you want your diffuser closer to the bottom of the tank to allow the co2 bubbles a longer time to diffuse. That close to the surface you are gassing off probably 90% or more of the co2 in less than a second. Do you use a drop checker? I always try to place my diffuser in the current or into the intake of the filter. Nice tank by the way.
To add to the above post, placing the diffuser so that the filter current pushes the bubbles around is beneficial as well. Increases the dwell time for the bubbles for better gas absorption.
I agree, you are wasting a lot of CO2 by having it that close to the surface / having bubbles off gas.

Place it lower in the tank and in a high flow area to distribute the bubbles everywhere and increase the contact time with the water.
I too concur with the placement of the diffuser. The goal is to put that as deep as possible and in a place that keeps the bubbles pushed down into the water column.

The longer the CO2 bubbles are churned around in the water column the more CO2 is dissolving into the water as carbonic acid and the more carbonic acid means more carbon for your plants. (This is also why your PH drops with CO2 addition, carbonic acid lowers PH).

This is also a reason to upgrade to a CO2 reactor to get more churn and more dissolve
Only to a point. A single diffuser can provide enough for a large tank (180 gallons) it just needs to be placed in the right spot to maximize efficiency.

Also, direct CO2 bubbles toughing leaves is the single best way for plants to utilize the CO2.

So the argument can go both ways ;)
yes it can.. A reactor is more efficient overall and more reliable IMO.. I've had issues with diffusers... getting plugged or watching bubbles drift to the surface and end up in the air.

As for CO2 directly on leafs. If your diffuser is distributing CO2 bubbles thoroughly to the underside of leafs across an entire aquascape then yes, but IMO in the name of efficiency and predictability I do recommend reactors and dissolving CO2 into the water column.
Exactly the reasons I run a reactor and not a diffuser ;)

Well, I have a low pressure regulator so diffusers literally don't work with my setups, instead I run low pressure into an inline reactor.

I just wanted to make sure OP knows that diffusers will work without issue on larger tanks, and have certain benefits that reactors cannot achieve.
Thanks a lot guys. I just don't like too much bubbles when it is below the filter current flow. What i can do is that i place the diffuser as below as possible but then the heater will come on top before the bubbles touch the surface. At bottom there will be defuser and on top there will be heater above it or if i need to put defuser and heater at different places and there should be no obstruction by the heater between bubbles and surface?
 
An obstruction between the bubbles and the surface is not a bad thing. Anything to slow them down; it’s a waste if they go straight to the surface. A decent flow should remedy this.
 
Thanks a lot guys. I just don't like too much bubbles when it is below the filter current flow.

That is the main issue people have with diffusers. They create "soda" water from all the micro bubbles being blown around the tank. But, this is the best way for CO2 to stay in contact with water = more time to dissolve.

If you don't want any bubbles in the tank, an inline reactor is your best bet. This needs to be used with a canister filter or an external inline pump.
 
An obstruction between the bubbles and the surface is not a bad thing. Anything to slow them down; it’s a waste if they go straight to the surface. A decent flow should remedy this.
So what i thought is to put defuser at bottom and place heater on top. Bubbles will go up and touch heater before they go to surface. Please let me know if its ok.
That is the main issue people have with diffusers. They create "soda" water from all the micro bubbles being blown around the tank. But, this is the best way for CO2 to stay in contact with water = more time to dissolve.

If you don't want any bubbles in the tank, an inline reactor is your best bet. This needs to be used with a canister filter or an external inline pump.
That's why i keep my defuser on other corner away from where the filter is. My plants are growing heavily and carpet pearls so I guess I am fine. Carpet pearls only when co2 is on. I tested that.
 
did everyone stop putting their cos outlets into their filter intakes? lol
 
So what i thought is to put defuser at bottom and place heater on top. Bubbles will go up and touch heater before they go to surface. Please let me know if its ok. That's why i keep my defuser on other corner away from where the filter is. My plants are growing heavily and carpet pearls so I guess I am fine. Carpet pearls only when co2 is on. I tested that.



Yes, but you’re sacrificing efficiency (it bothers some people, other people don’t care because CO2 is cheap) by having the bubbles rapidly rise to the surface to offhand instead of being pushed around the tank to dissolve and come in direct contact with the plants.

I agree though, I’m not a big fan of the sofa water look of micro bibles everywhere.
 
did everyone stop putting their cos outlets into their filter intakes? lol
I have a high tech setup but my filter is hob and i don't have a canister filter because my tank is not big and i don't need a bigger filter. I am having a basic co2 setup and don't like if i see small bubbles in all over my tank.
Yes, but you’re sacrificing efficiency (it bothers some people, other people don’t care because CO2 is cheap) by having the bubbles rapidly rise to the surface to offhand instead of being pushed around the tank to dissolve and come in direct contact with the plants.

I agree though, I’m not a big fan of the sofa water look of micro bibles everywhere.
Yeah it doesn't bother me at all. Co2 is cheap. I was paying too much for flourish excel for my low tech setup. This tank lasts 3 months while flourish one bottle which is of equivalent price lasta for one month only. I can increase the co2 supply and don't care if it is wasted. Will see. Today will put defuser as below as possible and heater on top of it.
 
you are going to have to watch your plant growth to determine if that is ok. Also check to see if you're getting a PH drop during the day indicating CO2 in the water column.

My only observation with diffusers is all the bubbles going straight to the surface. Which brings us back to reactors.
 
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To me, it looks like a lot of wasted CO2. But, the only way to know for sure is check pH drop.

Both placement of the diffuser, and the quaility / size of the bubbles are, in my opinion, no good. The only way to dissolve CO2 into the water, is more time in contact with water and good flow around the saturated spot. Both of which you do not have at the moment.
 
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