Co2 Profile and water changes on new scape

Hudson

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I'm currently trying !!! to fine tune my Co2 on a 4 week old scape but finding it a tad difficult due to having to do water changes every other day to deal with a algae outbreak.

I set the scape 5 weeks ago on Saturday, during the second week i had a faulty light timer while i was on late shift and for 3 days the scape had no light but loads of Co2 being pumped in (no livestock).

This caused an outbreak of BBA on the wood and Java Fern/Buce and green slime/fuzz on the monte carlo and stem plants and I've been fighting them ever since then.

Over the last 3 weeks of lockdown i've been trying to get control of things with 90% water changes every other day and spot dosing with excel on the BBA and syphoning the Green Slime/Fuzz algae out. Once i get into day 2 the Slime/Fuzz algae starts to take over and i need to do a water change although I'm starting to win with the BBA

Any how this is setup and current Co2 profile

ADA 60p
ADA Solar 1 @ 30cm above tank
Oase Biomaster thermo 350, 3 x pre fillters 1 x Large Blue, 2 x half tray Matrix 1 x Floss
Co2 Art Reg wit FE, Twinstar Diffuser.
Eheim Surface Skimmer
Daily Dose of Ei @ aquarium plant liquid mix amounts of 10ml alternative days rest sat

Tank Kh = 6
Tank Ph = 7.4 Before lights on

Tap Kh = 4
Tap Ph = 7.5 after 24hrs or 6.8 before degass.

Co2 Profile is as follows (day after water change)

7.4 @ 12pm
6.7 @1pm
6.6 @2pm (lights on)
6.5 @3pm
6.5 @ 4pm (drop checker green)
6.6 @5pm
6.6 @6pm
6.6 @7pm
6.6 @8pm
6.6 @9pm (Co2 off @9.30pm)
6.6 @10pm (lights off)


Ideally based on a tank Kh of 6, I should be aiming for a ph at lights on of 6.8 but the drop checker is not lime green more a bottle green. The drop checker only gets lime green at 6.6 suggesting a kh of 5 !!

I'm stuck as to why the drop checker and PH/KH don't tally up and wondering where the issue is

I've got a good quality Ph pen that is calibrated prior to use with both Dkh 7 and 10 and always stored wet.

TDS of tap is 160 and tank about 190 which a Kh 5/6 but that tds could be anything not just cal/mg.

Are the water changes the fault as the 2dkh diffrence on a 90% water change may be casuing ph/kh swings damaging plant tissue and triggering the out break in algae.

The one thing i will add is that bio master does have the old style head and i get large amounts of trapped air which i manually shake out daily this will no doubt cause a flux in Co2 flow and distrubution. I was due to get the nes style head before the lockdown but thats currently on hold and i only have 5 amano shrimp and 1 horned nerite as CUC due to the lockdown as well which has not helped.

Cheers for reading and any help or suggestions

Take care
 
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Zeus.

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I set the scape 5 weeks ago on Saturday, during the second week i had a faulty light timer while i was on late shift and for 3 days the scape had no light but loads of Co2 being pumped in (no livestock).

This caused an outbreak of BBA on the wood and Java Fern/Buce and what i though was diatoms on the monte carlo and the and I've been fighting them ever since then.
Unlikely as if you had no light on you just did a short 'virtual blackout', the lights being off for 3days was coincidental IMO and has reduced the outbreak of BBA etc.

pH profile looks GOOD :thumbup:

Ideally based on a tank Kh of 6, I should be aiming for a ph at lights on of 6.8 but the drop checker is not lime green more a bottle green. The drop checker only gets lime green at 6.6 suggesting a kh of 5 !!

I'm stuck as to why the drop checker and PH/KH don't tally up and wondering where the issue is

I've got a good quality Ph pen that is calibrated prior to use with both Dkh 7 and 10 and always stored wet.
Dont get caught up with the numbers and trust the DC colour as its the [CO2] is all that matters, doesnt matter what the actual kH, gH or pH is!!

Stable pH for photo period is the aim, but as 'Clive' says flow/turnover is KING

Oase Biomaster thermo 350, 3 x pre fillters 1 x Large Blue, 2 x half tray Matrix 1 x Floss
I would take the Floss out and most of the matrix, as they give the biggest reduction in output off the filter. Do pH profile again as better flow will affect the profile ;)

ADA Solar 1 @ 30cm above tank
Nice Light :thumbup:, but powerful. IMO this is the most likely culprit!, Can you dim it or raise the height? if not some floating plants would help reduce the intensity, however with 'lockdown' and with the pandemic at its peak stay at home OFC, some lego in the tank (or other floating particles/blocks) would also reduce the intensity whilst the outbreak gets under control.
 

Jayefc1

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The ph seems pretty stable all.the way through the light.period but seems to me it's not dropped enough there for I'd up the rate a little you need a drop of 1 for a good sold 30ppm o dont even check my kh /gh any more along as I get the drop of 1on my ph profile I'm happy and it stays at that till lights off
 

Hudson

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The ph seems pretty stable all.the way through the light.period but seems to me it's not dropped enough there for I'd up the rate a little you need a drop of 1 for a good sold 30ppm o dont even check my kh /gh any more along as I get the drop of 1on my ph profile I'm happy and it stays at that till lights off
Cheers for the reply.

Thats where i got a little confused, KH/PH table suggest a 1 ph drop from 7.4 down to 6.4 would give me toxic to livestock levels of Co2.
 

Hudson

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Unlikely as if you had no light on you just did a short 'virtual blackout', the lights being off for 3days was coincidental IMO and has reduced the outbreak of BBA etc.

pH profile looks GOOD :thumbup:



Dont get caught up with the numbers and trust the DC colour as its the [CO2] is all that matters, doesnt matter what the actual kH, gH or pH is!!

Stable pH for photo period is the aim, but as 'Clive' says flow/turnover is KING



I would take the Floss out and most of the matrix, as they give the biggest reduction in output off the filter. Do pH profile again as better flow will affect the profile ;)



Nice Light :thumbup:, but powerful. IMO this is the most likely culprit!, Can you dim it or raise the height? if not some floating plants would help reduce the intensity, however with 'lockdown' and with the pandemic at its peak stay at home OFC, some lego in the tank (or other floating particles/blocks) would also reduce the intensity whilst the outbreak gets under control.

Cheers for the reply

Will make the changes to the filter today and reprofile tomorrow.

Yeah the light is getting replaced once we get out of lock down, to raise the light any higher i will need to make a shade but cannot get materials.
 

Zeus.

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but cannot get materials
got any bubble rap?? temporary fix some between light and tank with bits of string/ washing line pegs etc

Could use a plastic bag below light as above. ( one of those really tin ones and use a single piece/sheet of it)

Make sure light still gets good ventilation and bubble rap/plastic bag or what ever you have to hand doesnt touch or get close to light.

If you have a glass cover just sellotape plastic bag to glass cover ;)
 

Hudson

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I've ordered some 2mm thick craft foam yesterday from the bay and it should be with me the middle of next week and i will make a shade.

How much higher do you think i should raise the light ? 5cm
 

Zeus.

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I've ordered some 2mm thick craft foam yesterday from the bay and it should be with me the middle of next week and i will make a shade.

How much higher do you think i should raise the light ? 5cm
Intensity at different distances:

inverse_square_law_formula_3.png



so at 30cm say intensity is at 100%
so at 35cm the intensity 'x' is-

x/100 = (30x30)/(35x35)

x=((30x30)/(35x35))x100 = 73.5% so 26.5% reduction in light from height of 30cm

rise the light 10cm to 40cm

x/100 = (30x30)/(40x44)

x=((30x30)/(40x40))x100 = 56.25% so 43.75% reduction in light from height of 30cm

Its a judgement call and depends on how the tank is responding to the measures you have done already done which will take time to show also, also depends on how easy it is the raise the light, if raising it 5cm is easy and 10cm is hard I'd go for 5cm, if 10cm is just as easy I go for 10cm, you can always adjust it further up/done as you see fit
 

Hudson

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Cheers again for helping.

I've managed to make a adhock shade using a old piece of Yoga matt and moved the light to 30cm as i actually had it set at 24cm.

Will feedback in a few days and see how things are going
 

Hudson

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Well i thought things where starting to settle but came across three major issues today.

The biomaster 350 has been getting worse for trapped air, I had removed it today to clean the pre filters and left it in the kitchen while i done a small amount of trimming
When i eventually got round to cleaning the pre filters the was a puddle on the floor !!!!
Turns out the the seal on the head is leaking !! Luckily i had a old fitlosmart from a new stripped down nano scape. It's not ideal for flow but will have to do until i can resolve the issue on the 350.

The Co2 art regulator solenoid valve screw had worked loose and was giving me a different bps rate every day and caused a bit a flux hour to hour

Lily pipes and 16/22mm pipe are pain in the butt.
 

aquascape1987

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Cheers for the reply.

Thats where i got a little confused, KH/PH table suggest a 1 ph drop from 7.4 down to 6.4 would give me toxic to livestock levels of Co2.
Hi mate. I’m currently doing the same at the minute, attempting to fine tune my CO2. Just had delivered today a Hanna pH probe and also Hanna alkalinity meter. Can you recommend a good PH/KH chart to use?

Currently, I’ve found one on a sticky thread on The Barr Report, but reading the thread, TBarr says that he uses a different one, but doesn’t appear to have posted it.
 

Hudson

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Hi mate. I’m currently doing the same at the minute, attempting to fine tune my CO2. Just had delivered today a Hanna pH probe and also Hanna alkalinity meter. Can you recommend a good PH/KH chart to use?

Currently, I’ve found one on a sticky thread on The Barr Report, but reading the thread, TBarr says that he uses a different one, but doesn’t appear to have posted it.
I've been using this one of the aqaurium wiki page.

http://www.theaquariumwiki.com/wiki/File:CO2_chart1.png
 

dw1305

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Hi all,
Just had delivered today a Hanna pH probe and also Hanna alkalinity meter. Can you recommend a good PH/KH chart to use?
I'd only use the pH probe with a drop checker, the problem with the alkalinity meter is that it shows all bases, rather than just the carbonate. Once you are happy with pH drop you can use that.

The advantage of the drop checker is that you know the fluid is 4dKH and doesn't contain any other bases. Particularly if you are using tap water in the tank you may get changes in dKH as the water supply source changes.

cheers Darrel
 

aquascape1987

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Hi all, I'd only use the pH probe with a drop checker, the problem with the alkalinity meter is that it shows all bases, rather than just the carbonate. Once you are happy with pH drop you can use that.

The advantage of the drop checker is that you know the fluid is 4dKH and doesn't contain any other bases. Particularly if you are using tap water in the tank you may get changes in dKH as the water supply source changes.

cheers Darrel
Yea I’ve found out this morning. Big difference in dkh of tank water vs tap water. Think it may be Chlorine in the tap water, as it mentions chlorine will throw results off in the manual. Tank water has de chlorinator added at water change and the water I’m testing from the tank is a week old, right before water change. I imagine the ferts I’ve added over the week will have affected this as well.

For me, I’m going to use the alkalinity vs ph table only to dial in the initial setting to 30ppm (30ppm according to the results and table). Then increase from there slowly and judge the final injection rate based upon stable ph profile across the photo period, affect on plant health/growth and effect on critters.

From what I’ve understood about estimating CO2 using alkalinity vs pH, other buffers (if that’s the correct term) being present in the water in addition to carbonate, thereby increasing the dkh test result, will result in an overly optimistic estimation of CO2? So if I use the initial result to get the first dial in point, then increase from there based upon critter and plant reactions, this should be safe for the critters. Hoping my understanding and logic on this is correct :nailbiting: I am using a drop checker also.

I’m going to start my own thread on this once I have some results, so as not to hijack this thread. Apologies @Hudson for hijacking a little bit already with my comment. Will be watching for your updates on this one :)
 
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dw1305

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Hi all,
For me, I’m going to use the alkalinity vs ph table only to dial in the initial setting to 30ppm (30ppm according to the results and table). Then increase from there slowly and judge the final injection rate based upon stable ph profile across the photo period, affect on plant health/growth and effect on critters.
I'm not a CO2 user, but that sounds a plan. I'll cc. in @Zeus. as he has <"practical experience"> and there is @Carpman <"New scape pH profile"> thread as well.
From what I’ve understood about estimating CO2 using alkalinity vs pH, other buffers (if that’s the correct term) being present in the water in addition to carbonate, thereby increasing the dkh test result, will result in an overly optimistic estimation of CO2?
I think that is what Tom Barr @plantbrain said, have a look at this one <"amount of CO2....">.

This recent thread <"Determination of CO2......"> isn't finished (in other words we don't have an answer) but it looks at whether "30 ppm CO2" really is 30 ppm CO2.

I'd be honest the more I read about the chemistry of dissolved CO2 the more it confuses me.

cheers Darrel
 

Hudson

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Yea I’ve found out this morning. Big difference in dkh of tank water vs tap water. Think it may be Chlorine in the tap water, as it mentions chlorine will throw results off in the manual. Tank water has de chlorinator added at water change and the water I’m testing from the tank is a week old, right before water change. I imagine the ferts I’ve added over the week will have affected this as well.

For me, I’m going to use the alkalinity vs ph table only to dial in the initial setting to 30ppm (30ppm according to the results and table). Then increase from there slowly and judge the final injection rate based upon stable ph profile across the photo period, affect on plant health/growth and effect on critters.

From what I’ve understood about estimating CO2 using alkalinity vs pH, other buffers (if that’s the correct term) being present in the water in addition to carbonate, thereby increasing the dkh test result, will result in an overly optimistic estimation of CO2? So if I use the initial result to get the first dial in point, then increase from there based upon critter and plant reactions, this should be safe for the critters. Hoping my understanding and logic on this is correct :nailbiting: I am using a drop checker also.

I’m going to start my own thread on this once I have some results, so as not to hijack this thread. Apologies @Hudson for hijacking a little bit already with my comment. Will be watching for your updates on this one :)

No Problems on the hijack as it has added the the orginal question i asked.

I'm currently awaiting a new head for the biomaster to be shipped to me from Oase, without this i'm struggling with turnover and keep getting spikes in Co2 over the day.

As a short term measure i've dialled the Co2 back to around about a Ph 6.8 as this gives the least amount of swing over the photo period.
 

sparkyweasel

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using alkalinity vs pH, other buffers (if that’s the correct term) being present in the water in addition to carbonate, thereby increasing the dkh test result, will result in an overly optimistic estimation of CO2?
My limited understanding is that that is the case if there are other alkaline buffers present. But if there are acid buffers present* those could have the opposite effect. If both are present they will have to fight it out and things could get really complicated. :)
So I would start with a conservative injection rate, not trying to get close to maximum at the beginning. Then make small increases when able to observe the reaction of the livestock.

*eg: from bogwood or substrate.
 

Zeus.

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ea I’ve found out this morning. Big difference in dkh of tank water vs tap water. Think it may be Chlorine in the tap water, as it mentions chlorine will throw results off in the manual. Tank water has de chlorinator added at water change and the water I’m testing from the tank is a week old, right before water change. I imagine the ferts I’ve added over the week will have affected this as well.
Doesn't surprise me as 'test kits' aren't reliable and some of the hardscape/ferts in your tank may be changing your dkH

For me, I’m going to use the alkalinity vs ph table only to dial in the initial setting to 30ppm (30ppm according to the results and table).
Which if fine if your pH meter is 100% accurate, however mine isnt so I just use the DC colour change as its easy no calibration required and works independently of anything else in the tanks water. Do'nt even calibrate my probes any more as I fail to see any advantage its just a waste of time as the results changes nothing for me, its just a number, but when the DC is green it tells me the tanks [CO2] is about 30ppm, take pH record/note the 'number', the pH 'number' is just a reference point once the DC has changed colour after 2hrs, then try and get the pH 'number' to be stable from lights on till CO2 off via pH profile - easy. Hopefully you have good flow/turnover in your tank which will help stablise the [CO2] though out the whole tank, flow is king in the CO2 injected tank ;)

based upon critter and plant reactions
When too high the fish will be gasping for air, if no fish the snails will all be at the top of tank.

I'd be honest the more I read about the chemistry of dissolved CO2 the more it confuses me.
IDD, thats why a like the DC for [CO2] takes all the chemistry/dkH/pH out of the equation IMO :thumbup:
 

aquascape1987

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I’m pretty confident the test is accurate, as I can replicate the tests 3 times, all coming in within 1 or 2 ppm of each other. And by anyones standards, 1 part in a million is pretty darn accurate! It’s not me reading the colour, you put the sample inside and the device reads it, by itself electronically. Plus, you can verify with a test of a calibration fluid of a known dkh. Again, it comes in within 1 or 2 parts per million. I would say that’s like hitting a bulls eye with a sniper rifle, at 3 miles out.

pH meter is also accurate. It replicates readings consistently, and tests to within 0.01 pH of both buffer solutions between tests. I am using the drop checker as well though, as this is the way I have always done it.

Flow and turnover for me are exceptional, so should be ok on this front. I’m running 2 x Eheim pro 4 250 Thermo filters on an 85 litre tank, feeding through spray bars on back wall of tank. So combined, this is 1900 litres per hour turnover according to the ratings of the filters, and distribution of flow is even around all areas of the aquarium.

From what I’ve measured today in terms of the variance in dKH results between tap water and my week old pre water change tank water, it looks like I’m going to have to take the dKH at the start of every day when pH profiling. I think it’s the only way to get meaningful results when using the pH/ alkalinity table method. I do however, think that if you do this, the results will be meaningful, and will help in zeroing in on the correct injection rate, when referenced against the drop checker, and achieving a stable pH profile. And then as you say, the pH numbers will just become a reference point, rather than a set in stone number to aim for. Each days target pH value will likely be different, depending on the alkalinity.

I think the key is getting stability of pH throughout the photo period, after the initial drop ,and then tweak from there, to get to the upper limit that will be tolerated comfortably by the livestock.

I’ll post my own thread with my detailed results after I have a pH profiles for 3 consecutive days. This will be based upon my co2 as it has always been since I set it using the drop checker. It’s at this point I am going to start to tweak the injection rate.
 
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