CO2 - stable pH question

[Twisted Melon]

Hi,

After reading more in the last 2 weeks than I have since I was in school, there are still a few things that I haven’t quite got my head around.

Firstly the method of setting up my CO2 and what the goal is?

Is this correct?

I’m aiming for around a 1 point pH drop when the CO2 is on to get to around 30ppm. Monitor by drop checker or pen. And I need to adjust the injection rate so I attain this level by the time the lights go on? Getting to the desired level will vary in time depending on tank size, water flow etc?

Do I need to adjust the time CO2 comes on earlier to allow for ambient room daylight in a bright room as photosynthesis will possibly start before aquarium lights go on? I ask as my tank is in a north facing conservatory. No direct sunlight at all but it is obviously brighter than a room with one small window.

I then want the CO2 / pH to remain at that level for the lighting period until around an hour before lights out?

How do I determine when to turn off the CO2? Some say an hour before lights out, others 2.

Do I need to continue to monitor CO2 / pH once the lights are off or will the water just return to its previous levels and I can stop thinking about it?

Also, when I first get setup, I’ll have my aqua soil in (I’ve decided ADA), my CO2 setup, ferts etc. ready to go. Plants are in, water will be doing it’s cycle.

Do I start on low CO2 and low lighting? Or full CO2 and full lighting? Or full CO2 and low lighting? I presume ferts are at the expected level for my volume from the get go?

I know these questions will have been answered in various places already, but it can be difficult to find things. And my wife says if I don’t stop reading this forum for about 6 hours a night, she’ll make me move into the tank!

Thanks in advance.

 

[ian_m]

Firstly the method of setting up my CO2 and what the goal is?

Yes get CO2 sorted whilst tank is cycling and no fish are present.

You are aiming for green drop checker and/or 1pH drop for when the light comes one. This means starting CO2 injection roughly 2 hours before lights come on. Some poeple manage in 2 hours, some 1 1/2 hours some 2 1/2 hours. Generally I have found 2 hours before lights on gives me a green (slight yellow ) drop checker at lights on that stays that colour for the whole of the lighting period.

Do I need to adjust the time CO2 comes on earlier to allow for ambient room daylight in a bright room as photosynthesis will possibly start before aquarium lights go on? I ask as my tank is in a north facing conservatory. No direct sunlight at all but it is obviously brighter than a room with one small window.

No. My tank gets a lot of window light in the morning and I have never had algea or plant issues due to this light. Recently someone started a thread about his poor plant health due to him assuming lack of CO2 when lights were off. I have never heard anyone else ever having this issue ever. Anyway there will be atmospheric CO2 present in the water at about 1ppm, even when you don't inject CO2 and people have used this level to CO2 to grow plants successfully and algea free with low light levels for years, without having to add extra carbon sources.

I then want the CO2 / pH to remain at that level for the lighting period until around an hour before lights out?

Yes by adjusting injection rate and surface aggitation you want to achieve green drop checker and constant pH during lights on period. Varying levels of CO2 during light period cause poor plant health and leads for algae rearing its head.

How do I determine when to turn off the CO2? Some say an hour before lights out, others 2.

You dont really. Most people turn off 1 hour before lights off, with no issues. If you are having a worry, waste some CO2 and turn off CO2 at lights off. I turn my CO2 off 1 hour before lights off and have an air pump coming on 15 minutes before lights off. This very quickly removes CO2, as I can see the drop checker loosing its green colour and have not suffered plant health issues.

Do I need to continue to monitor CO2 / pH once the lights are off or will the water just return to its previous levels and I can stop thinking about it?

As my gran used to say "stop wasting your worries".

Do I start on low CO2 and low lighting? Or full CO2 and full lighting? Or full CO2 and low lighting? I presume ferts are at the expected level for my volume from the get go?

For a new tank, dose ferts full level from day one. Dose CO2 at full level from day one. However keep light level low and shorter time. I started my high tech tank with Ye Olde low light level T8 tubes, with the reflectors bent round to lower light levels, on for only 4 hours for first couple of weeks to allow plants & tank to settle down. Got impatient and turned reflectors round for full T8 light and suffered an immediate diatom outbreak...luckly this was scoffed almost immediately by my Ottos. Now I am using 4 off T5 tubes in very high light levels, plants grow light crazy and as my CO2 has taken years to get sorted, no algea or plant health issues at all.

 

[Twisted Melon]

Thanks for such a detailed reply Ian! Much appreciated.

You say “Varying levels of CO2 during light period cause poor plant health and leads for algae rearing its head.” in one of your replies.

How do I make sure it stays stable? What are the pitfalls people fall into in this regard? You can’t be changing injection rates during the day surely?

You also say it took years to get your CO2 sorted? Really?! That’s a bit scarey for a newbie! What struggles have you had?

Thanks again Ian!

 

[ian_m]

How do I make sure it stays stable? What are the pitfalls people fall into in this regard? You can’t be changing injection rates during the day surely?

Experience and learning with your tank is what it takes. Best done with no fish. Thought to be honest, a friend of mine , honest, injected too much CO2 (he told me ) and the loaches lay on the bottom and other fish gasped at top of tank. Whoops. Putting on air pump, within minutes returned all fish back to normal.

This is not really what you want to acheive, but as you can see fish completely unaffected, so there can be quite a bit of leeway on drop checker colour.

This is better, possible slightly yellow....

I find the JBL drop checker much much better than any of the fancy pancy glass jobbies. Couple of reason reasons.
- Much cheaper.
- Has white insert so can easily see drop checker fluid colour.
- If you drop it, pick it up and carry on. Unlike glass ones.
- Easier to clean without it breaking.

You will (eventually...) find your level of CO2 injection (mine is about 2 bbs in my bubble count) and the angle of your spray bar that gets you a green drop checker.

So start low and increase slowly by changing injection rate and spray bar angle/surface aggitation.

I use 0.015gr/litre/hour in my tank for the green/yellow drop checker. ie if your tank is 200litres and CO2 time is 8 hours that us 0.015 x 200 x 8 = 25gr per day. Use a set of scales to weigh my fire extinguisher so I know how much is being used. I get about 100 days odd for a 2KG FE into 180litre tank.

This is my angle of spray bar I used in 2013. Possibly a bit lower now, to get a higher CO2 level to match my much greater light level (4 x T5 tubes).

 

[Twisted Melon]

Great info again!!

Would you recommend a spray bar for the output over other options?

Thanks so much. Things are finally starting to click.

 

[ian_m]

Would you recommend a spray bar for the output over other options?

Yes. Just make sure covers whole width of back of the tank and the filter flow rate is rated at least 10 times the tank volume. My filter is a JBL1501 @ 1400litres/per hour, into a 180litre tank along with the Juwel internal filter of 600litres/hour. I also have a 3200l/hr power head, as despite using these two filters, there were places in the tank where the drop checker stayed blue and algae appeared on plants, showing poor CO2 distribution.

CO2 just not easy to implement in practice, takes a lot of fiddling and experimentation to get it right. Get it wrong, especially in high light situations, and in a matter of days plants quickly suffer and algae moves in for the kill.

 

[Danny]

Do I need to adjust the time CO2 comes on earlier to allow for ambient room daylight in a bright room as photosynthesis will possibly start before aquarium lights go on? I ask as my tank is in a north facing conservatory. No direct sunlight at all but it is obviously brighter than a room with one small window.

For the last few days I have timed my co2 to the ambient/natural light, in my mind if the plants are receiving enough light for photosynthesis then I should have the co2 timed to match it.

No proven mechanics behind it just my own theory which happens to be totally different to the given method, but I see it quite simply that they are awake so feed them.

If you look at the plants they will open and close throughout the day based on the light they receive, open "awake" closed "asleep".

We aim to feed the plants (co2) when they are awoken by turning our tank light on so have co2 linked to the tank light, BUT if they are being woken by natural/ambient light surely it's the same difference and they should be fed.....

As I said just my theory and something I'm trying, if in a month of doing it I have a notable difference compared to the last 2 months I'll know I have something more than a theory.

Some people run co2 24/7 so different strokes for different folks.

 

[Twisted Melon]

Yes. Just make sure covers whole width of back of the tank and the filter flow rate is rated at least 10 times the tank volume. My filter is a JBL1501 @ 1400litres/per hour, into a 180litre tank along with the Juwel internal filter of 600litres/hour. I also have a 3200l/hr power head, as despite using these two filters, there were places in the tank where the drop checker stayed blue and algae appeared on plants, showing poor CO2 distribution.

CO2 just not easy to implement in practice, takes a lot of fiddling and experimentation to get it right. Get it wrong, especially in high light situations, and in a matter of days plants quickly suffer and algae moves in for the kill.

That’s a lot of water movement Ian. How are your fish doing??

What fish do you have out of interest?

 

[Edvet]

That’s a lot of water movement Ian

Actually that's not "a lot", it's what is advised in any CO2 enriched tank

 

[ian_m]

That’s a lot of water movement Ian. How are your fish doing??

Fish are fine. They seem to swim quite a lot in the flow, but manage to find slower flow bits to just float there when they feel like it.

What fish do you have out of interest?

Mostly easy keep fish, cardinal tetras, other tetras, some mollies that breed like rabbits and a few other odd fish.

 

[Twisted Melon]

Pretty much the fish I’m going for Ian. Do you keep your water on the soft side?

 

[Twisted Melon]

My tank will be 284 litres. Will a Fluval fx6 be able to create enough flow with a spray bar? It’s rated at 3500 lph, which obviously is more than the 10x suggested here, but I know you have to allow for restrictions of your decor an the plants themselves.

 

[ian_m]

Do you keep your water on the soft side?

No my water is 22' clarke and rock hard. Scale was everywhere in the house until I got a whole house water softener. Hardwater generally doesn't affect fish or plants. I certainly don't have issues. Occasionally I wipe the T5 light tubes with vinegar to remove scale splashes.

Will a Fluval fx6 be able to create enough flow with a spray bar?

Yes plenty enough, but larger non standard pipe sizes ie not 16/22 means great thought and cleverness have to be applied in a planted tank.

See Zeus's fantastic tank (and his super PLC controller) for how to cope with FX6's non standard pipe sizes and not reduce the flow.
https://www.ukaps.org/forum/threads/olympus-is-calling.43046/

The x10 rule is the nominal tank size and the manufacturers side of box rating for the filter.

In practice you will loose 10-20% water volume due to hardscape as well as actual real world dirty filter being possibly only 50% flow rate of that quoted on the side of the box, so x10 is a good rule of thumb.

 

[Twisted Melon]

Yes plenty enough, but larger non standard pipe sizes ie not 16/22 means great thought and cleverness have to be applied in a planted tank.

Yeah that sounds like more trouble than it’s worth!!

So back to trying to work out what filter to get. Any suggestions for a filter that outputs around 3000lph that has standard size hoses?

Cheers.

 

[ian_m]

You wont find a filter that does more than approx 1500l/hr using 16/22 hoses as these would restrict the flow too much. So if you want a single filter then you have to have bigger hoses. Jbl1900 is 19mm, fx6 is 25mm.

See Zeuses journal how he fitted 16mm fittings to his fx6 without losing flow.

 

[Zeus.]

If you have the space I would advise an APS EF for use as a CO2 reactor with a bypass like I did on my tank, gets good flow good pH drop and tank bubble free CO2 wise. The FX6 is a beast of a filter and the non standard pipe has been a pain in the A$$

 

[Twisted Melon]

Cheers Ian.

Zeus. I read your entire journal last night and couldn’t see where you said about changing to 16mm without loosing flow on the fx6.

I’d been on the forum all night though so there’s a good chance my brain had melted.

Could you point me in the right direction please? What page was it on?

Thanks very much!

 

[Twisted Melon]

Just seen a flow diagram of your setup on anther post Zeus.

Can I ask why you linked the 2 systems together instead of just running the APS on its own as a reactor? What is the benefit of the Fluval and the APS being linked together by your bypass?

Cheers

 

[Zeus.]

Initially I had the inline atomizers pre filter and on the independent line with the eheim 3000 pump. to keep flow optimal I made a bypass on the atomizers as the FX6 uses 25mm piping and the atomisers use 16mm

which worked OK except I had a tank full of CO2 bubbles and if I had the CO2 injection rate too high on the FX6 line which was prefilter the FX6 would build up with CO2 then come out as large bubbles. I had the other independent line on a pH controler ( waste of money IMO - but handy)

So I swapped out for the JBL ProFlora direct CO2 Inline diffuser and was no better if not worse bubble wise with my high injection rate which for 500l tank needed to be high.

Then got on to the APS EF2 as a reactor, did the tests with both type of inline difusers and found the JBL one worked the best with the reactor.

The narrowest pipe in the APS EF2 was 12mm

so with using the the JBL post filter I didnt want to restrict the flow as FLOW is KING in planted Tanks. Plus I didnt want the flow to high in the reactors so it didnt push the CO2 bubbles down too fast. So I did the bypass with a Valve so I could adjust it or close it. Then found it worked well with low flow though the reactors getting a great pH drop. I did start using more CO2 at the same time but I was getting a bigger pH drop in the tank as thats what I was after - DC goes clear but before it was only going green/light yellow. Was after a higher CO2 ppm at the time as well, so hard to compare how much CO2 I was using pre reactors as I had increased the [CO2] in the tank. I did run the CO2 use pass Clive (our CO2 guru at UKAPS) at the time and compared to the CO2 he used on his 700l tank mine was in the same relative range so I accepted the high CO2 usage.

so plumbing ATM

So can control the flow though the reactors to suit my needs.

Why two reactors - well that way I can have a MASSIVE initial CO2 injection rate

get the pH drop in 42mins then have one turn off and then one maintains the pH all bubble free in tank

Just seen a flow diagram of your setup on anther post Zeus.

Can I ask why you linked the 2 systems together instead of just running the APS on its own as a reactor? What is the benefit of the Fluval and the APS being linked together by your bypass?

(Just update Journal so diagram in there sorry I should of added it)

The APS filter has no pump on it so the FX6 pushes the water though it, the APS is basically a bubble trap.

Also at the time I did add the reactors I was planning on reducing the usage of the independent line and just using the FX6, but with aglea and growth issues ( some of which was only in my mind ) I never reduced the Independent ehiem 3000+ use except increased it. So I Could have the reactors on that line, but having the reactors post FX6 keeps them clean, had them on for months and only cleaned them once and they was spotless so only clean one, if I had the reactors post eheim 3000+ pump detritus would build up in them.

The bypass enables most of the water to bypass the reactors so keep great flow.

Hope that Helps

Zeus

 

[Twisted Melon]

Thanks for a great response Zeus.

Do you think it would work to have a fx4 instead of a fx6 running through a spray bar, then use a APS EF 2 as a reactor on a separate line on another spray bar. That would give me well over 3000lph at a reduced cost.

Would I need the CO2 coming out of both filter outlets or is the fact that the CO2 is present, and the flow sufficient that it doesn’t matter.

Or I could get 2 x 1500lph filters and not have to worry about oversize filter pipes.

Also, did you swap you tubing out for ones that the CO2 won’t perish?

What do you think?

Thanks again.