• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

Co2 timing with huge surface agitation.

F

Franks

Member
Joined
26 Aug 2015
Messages
310
In a nutshell I’ve fixed my canister filter and improved flow by at least double. I don’t need the wave maker anymore.

My co2 is inline via a JBL Pro diffuser and I think I’m off gasing too much but I’d like try and keep as much agitation as possible to see if much more o2 helps keep algae at bay.

Today I logged the following timeline and DC colour;

11.30-6pm Co2 on
2pm-8pm T5HO lights on

And here is the timeline;

11.30am Co2 on DC BLUE
2pm lights on DC BLUE
4pm DC LIME GREEN
5pm plants start pearling up nicely
6pm Co2 off DC LIME GREEN
8pm lights off DC LIME GREEN
9pm DC GREEN
10pm DC GREEN/BLUE


So from the above, it’s taking 4.5hrs for the drop checker to turn a nice lime green and the lights are off while I still have the tank loaded with Co2. That’s much longer than it’s ever taken to prime the tank with adequate co2.

The question is - should I simply shift the whole Co2 timings to coincide with lights on at 2pm? If I start Co2 at 9.30am then that’s the 4.5hrs it’s taking to dissolve into the water column. At the tale end, the Co2 is clearly dissipating by 9pm, 3 hours after Co2 off and 1 hour after lights off. Clear evidence that the plants are cruising along and using a large amount of the available Co2 in the water column.

What would you guys do given this evidence?

TIA











Sent from my iPhone using Tapatalk
 
Max [CO2] for lights on is critical. If it takes 4hrs it takes 4hrs. One of my tanks takes 3hrs. Yours takes 4.5hrs based on your DC. Problem is DC take their time to change colour up to 2hrs. Getting a cheap pH pen and doing a pH profile should be a better way of checking your CO2 is maxed at lights on and stable there after. Cheap pH pens are the best but good enough for doing a pH profile but soon need recalibrating. But easy to use the relative output to check stabity for photoperiod, just the actual pH won't be the same.
 
Yes, I’ve used one in the past with good results so will likely buy another to do the same to account for my improved flow and gaseous exchange.

I’ve been watching some ADU and Dennis Wong Co2 discussions on YouTube and both highly suggest that an advantage is created by creating a tank with high gaseous exchange. Sure it uses more Co2, but it’s much more stable when dialled in.

I’ve shifted the Co2 timing for today and will see how it goes. I’ll also get a pH pen ordered.


Sent from my iPhone using Tapatalk
 
Franks said:
much agitation as possible to see if much more o2 helps keep algae at bay.
Click to expand...
There is no evidence that doing this will keep algae at bay. Algae move in when you make a mistake and lack of O2 is not likely to be one of them. The surface agitation in CO2 injected tanks is to actually gas off some of the CO2, which stops the injected CO2 rising to fish unsafe levels. O2 will diffuse into the water based on the surface you have already. Not a worry.

The fact that your drop checker is not green when lights come on is you major "algae inducing" worry. Clearly you are doing something wrong. Algae will move in very quickly if you light your plants and they have no CO2.

It should take about 2 hours odd to get CO2 levels stable, a decent drop checker will respond in minutes, though it does depend on you CO2 flow and distribution. If drop checker is not near any flow, it will obviously not respond. Using a pH pen to gauge CO2 levels is much quicker.

So as a way forward, leave injection rate as it is, reduce surface agitation to allow more CO2 to stay in the water and watch the drop checker and fish behaviour.

See here for the maths behind injection and loss rates and why a certain level of degassing is needed.
https://www.ukaps.org/forum/threads/co2-concentration-versus-time-the-maths.51423/
 
Franks said:
My co2 is inline via a JBL Pro diffuser and I think I’m off gasing too much but I’d like try and keep as much agitation as possible to see if much more o2 helps keep algae at bay.
Click to expand...
This is another mistaken strategy and is fundamental error is in the assumption that Oxygen in the water will necessarily be increased by extreme agitation.

The truth is that aquatic plants eject Oxygen into the water column, so they actually saturate the water with Oxygen to a higher level that would be possible without plants. This extra Oxygen feeds bacteria and fauna and improves their health overall.

Excessively agitating the water defeats this purpose because not only will it off-gas CO2, but will also off-gas the Oxygen we work so hard to generate.
If too much CO2 is depleted then the plants will also produce LESS Oxygen. So this is a doubly poor decision.

Excessive agitation only makes sense at night when the lights have been off for some time and the Oxygen levels introduced by the plants are depleted.

While poor Oxygen levels do contribute to algal blooms, there are a lot of other factors that trigger the blooms, such as excessive lighting, poor flow/distribution and, more importantly, poor CO2, which ironically, may occur with excessive agitation.

Cheers,
 
That makes sense. I might look at lily pipes to try to control the outlet flow. Current flow isn’t breaking the water surface but the whole surface shimmers greatly and is even pushed up at the opposite face of the tank like a constant wave. Bizarrely, this doesn’t have a huge bearing on flow around the lower layers as the plants gently sway.

23a3d1114688c7ef4f87a9fda25d7324.jpg



Sent from my iPhone using Tapatalk
 
Mine DC'S, two of them hanging on the glass (left and right corner) are responding very late... They get lime green when lights are on for 3 hours or so? The ph profile says otherwise... Co2 2,5 hours on before lights (Kh 6 in tank)... and ph stays stable for rest of photoperiod.. what to trust? I think the ph pen...

I also have pretty "much" surface agitation... Eheim skim 350 on 24/7 and the lily pipe breaks the surface. Currently at 9 bps on a 128l tank... Previous scape with other lily pipes (not breaking surface) I had 5 bps (using JBL atomizer) and easy lime green DC.

I was considering putting the eheim skim off but after a talk with Wong he suggested higher bps with more agitation.

My ph pen was very cheap from China. I would get one ;)
 
Last edited:
Nigel95 said:
Mine DC'S, two of them hanging on the glass (left and right corner) are responding very late... They get lime green when lights are on for 3 hours or so? The ph profile says otherwise... Co2 2,5 hours on before lights (Kh 6 in tank)... and ph stays stable for rest of photoperiod.. what to trust? I think the ph pen...

I also have pretty "much" surface agitation... Eheim skim 350 on 24/7 and the lily pipe breaks the surface. Currently at 9 bps on a 128l tank... Previous scape with other lily pipes (not breaking surface) I had 5 bps (using JBL atomizer) and easy lime green DC.

I was considering putting the eheim skim off but after a talk with Wong he suggested higher bps with more agitation.

My ph pen was very cheap from China. I would get one ;)
Click to expand...

I’ve got one on order having used one in the past to dial a tank in. That ended up with the pen falling into the water and killing it

My BPS is huge too. Certainly too fast to count by eye but last night the DC was a nice shade of lime green after lights out. That was also having stopped co2 2 hours before lights out.


Sent from my iPhone using Tapatalk
 
Franks said:
I’ve got one on order having used one in the past to dial a tank in. That ended up with the pen falling into the water and killing it

My BPS is huge too. Certainly too fast to count by eye but last night the DC was a nice shade of lime green after lights out. That was also having stopped co2 2 hours before lights out.


Sent from my iPhone using Tapatalk
Click to expand...

I always film in slow motion for 1 Second. This make it easier to count bps.


Verzonden vanaf mijn iPhone met Tapatalk
 
You guys must be losing masses of CO2 due to poor injection, surface losses or otherwise. I run less than 2 bps (JBL ProFlora bubble counter) and get lime green drop checker into a 180litre tank. Any more, even slightly and I get.
upload_2018-5-9_14-23-44.png

Fish don't seem to mind, too much at this level, though some eventually do start gasping at the surface towards and of CO2 period :grumpy:, so time to back it off.

All a matter of carefully adjusting angle of spray bar, angle of other filters and powerhead(s) to ensure "sufficient" surface agitation and good water/CO2 distribution around the tank.

I use about 20gr CO2 per day for 8 hours CO2 on. A 2Kg FE lasts about 3 months (100 days).
 
Nigel95 said:
Soft or hard water? What KH?
Click to expand...
Very hard. 22dKH.

No idea on pH as I have had sufficient success using a drop checker all around the tank and have monsterously growing algae free plants, so haven't bothered. Knowing pH won't change anything.
 
ian_m said:
Very hard. 22dKH.

No idea on pH as I have had sufficient success using a drop checker all around the tank and have monsterously growing algae free plants, so haven't bothered. Knowing pH won't change anything.
Click to expand...

Get us all a few pics


Sent from my iPhone using Tapatalk
 
This the best I have at the mo. This is after a major balding, before going away on holiday.
upload_2018-5-9_15-50-53.png


This is what I came back to after leaving for 5 weeks. This was also with reduced lighting time & ferts dosing. My carpet was smothered...
upload_2018-5-9_15-52-10.png
 
You must log in or register to reply here.
Back
Top