# CO2 - stable pH question



## Twisted Melon (8 Feb 2018)

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.


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## ian_m (8 Feb 2018)

Twisted Melon said:


> 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.



Twisted Melon said:


> 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.



Twisted Melon said:


> 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.



Twisted Melon said:


> 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.



Twisted Melon said:


> 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".



Twisted Melon said:


> 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.


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## Twisted Melon (8 Feb 2018)

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!


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## ian_m (8 Feb 2018)

Twisted Melon said:


> 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).


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## Twisted Melon (8 Feb 2018)

Great info again!!

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

Thanks so much. Things are finally starting to click.


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## ian_m (8 Feb 2018)

Twisted Melon said:


> 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.


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## Danny (8 Feb 2018)

Twisted Melon said:


> 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.


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## Twisted Melon (8 Feb 2018)

ian_m said:


> 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?


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## Edvet (9 Feb 2018)

Twisted Melon said:


> That’s a lot of water movement Ian


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


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## ian_m (9 Feb 2018)

Twisted Melon said:


> 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.




Twisted Melon said:


> 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.


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## Twisted Melon (9 Feb 2018)

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


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## Twisted Melon (9 Feb 2018)

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.


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## ian_m (9 Feb 2018)

Twisted Melon said:


> 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.



Twisted Melon said:


> 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.


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## Twisted Melon (10 Feb 2018)

ian_m said:


> 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.


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## ian_m (10 Feb 2018)

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.


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## Zeus. (10 Feb 2018)

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$$


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## Twisted Melon (10 Feb 2018)

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!


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## Twisted Melon (10 Feb 2018)

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


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## Zeus. (10 Feb 2018)

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



Twisted Melon said:


> 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


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## Twisted Melon (10 Feb 2018)

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.


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## Zeus. (10 Feb 2018)

The fact your planning on a planted tank means you dont need the filtration of the FX6 as the Plants will do most of the filtration for you. Using the FX6 means you will have to spend money on pipe fittings which soon adds up. The FX6 is a BIG filter pretty heavy when full and bit of a pain to clean. But the FX6 is great value for money. Going for a smaller filter or two with compatible hose fittings could make life much easier short and long term. esp if you go for a filter takes easy to clean the media. I would say two smaller is better than one big one. Do you plan on a spray bay or lily pipes custom ones will be needed with the FX6 but with a smaller filter theres lots of options off the shelf that will fit without reducing the flow. Keeping you plumbing as simple as possible will make it easier to clean so your more likely to do it, my plumbing is very complex so doesnt get done often at all. normally clean the filter every week.

CO2 coming out of one filter outlet works fine if the flow in the tank works well

What size is your tank ?

6Kg cylinder of CO2 lasts me a month on my 500L with Big pH drop


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## Twisted Melon (10 Feb 2018)

Cheers Zeus. My tank is 285 litres so quite a bit smaller than yours. 

I was planning on a spray bar. 

Any suggestions on a filter I can get x 2 of that will do the jobs I need?


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## Twisted Melon (10 Feb 2018)

Another question. When you devote a filter to act as a reactor, is there anything you need to do to the filter? Like add media to slow the flow a bit? 

Cheers


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## Zeus. (10 Feb 2018)

Twisted Melon said:


> My tank is 285 litres so quite a bit smaller than yours.



Still a big tank to inject CO2 into



Twisted Melon said:


> a spray bar.



Good choice IMO



Twisted Melon said:


> Any suggestions on a filter I can get x 2 of that will do the jobs I need



Lots to choose from I would choose one that is easy to clean. The output of the filter doesnt have to be x10 the tank size ie 2850litres per hour. If so my 500l tank would fail with the FX6 as it would be well short of the x10 rule I make up the output by having an independent ehiem pump at 3000liters per hour. Its the combination of the flow from all pumps/powerheads/filter etc.  Plus the rule isnt set in stone its how well the water moves in the tank. Careful positioning of the spraybar makes a massive difference even down to the number and size of holes in the spray bar, if the holes are too big it will reduce tank turnoverover also if holes too small the output from the filter will be reduced and the turnover will be reduced. Its a case of trail and error,  with each tank being unique in its requirements dependent on what filter you get. I tried the FX6 with twin 20 mm outputs and it was rubbish Spraybar much better





My tank is a room divider so short side against the wall, most folk use a spraybar on the long back of tank




Twisted Melon said:


> When you devote a filter to act as a reactor, is there anything you need to do to the filter?



Well the filter you use to filter will just be normal it will filter, you dont need fine filter media as that will reduce the filter output, plus you dont really need ceramic filter media as in a planted tank your plants will be the biggest biological filter you have. Then the filter output feeds the inline atomiser, then it goes to the CO2 reactor (APS EF2 in my case) which can have course filter media in it to (I used BioBalls) but chopped up pan scrubbers do the trick at a great price


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## Twisted Melon (11 Feb 2018)

So let me see if I understand this setup. My filter - the one used as a filter - has the inline atomiser on its output line, then this line after the atomiser, feeds into the input of the filter being used as reactor?

Cheers


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## Zeus. (12 Feb 2018)

Twisted Melon said:


> So let me see if I understand this setup. My filter - the one used as a filter - has the inline atomiser on its output line, then this line after the atomiser, feeds into the input of the filter being used as reactor?
> 
> Cheers


Correct with the water going in at the top of the reactor

Sent from my Moto G (4) using Tapatalk


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## ian_m (13 Feb 2018)

If you are going to use two filters with handy standard sized tubing eg JBLe1501 with 16/22mm tubing, then you plumb it as below. Main points are two sections of spray bar and two needle valves to control CO2 rate to each filter. Connecting two filter inputs or outputs into one pipe is a big no-no, you must have seperate piping.



Another point to consider is electrical running cost. The JBLe1502 is 1400l/hr @ 20W. This works out 20/1000 * 0.17 * 24 * 365 per year = £30/year (@ 17p per KWhr electricity).

So buying a more efficient filter, but more expensive, can work out much cheaper in the long run. For example JBLe1501 is £150, AllPondSolutions 1400l/hr filter is £60 but 35W pump, thus £52/year running cost. So after about 3 years the JBL will have paid for the difference in price in electricity saving.


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## Edvet (13 Feb 2018)

`Still keep wondering about that fish in the bubble counter Ian


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## Twisted Melon (14 Feb 2018)

That’s a handy little diagram there Ian. Thanks very much.


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## Twisted Melon (14 Feb 2018)

Are those jbl filters easy to clean?


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## ian_m (14 Feb 2018)

Twisted Melon said:


> Are those jbl filters easy to clean?


I have a JBLe1501.

It has quick release hose attachment, below. You close the two levers on left and right of hose inlets/outlets, that closes valves shutting off flow. You then pull the center lever to release the whole hose attachment assembly. Easy peasy. No leaks.







Filter can then be pulled out of my cabinet easily and pump head unclipped. I then rinse almost weekly (if I remember) coarse filters F1 in the picture below. They tend to accumulate plant debris.





I clean the rest of the filter every couple of months by just rinsing the filters F4 & F5 in fish water and the three half filled trays of ceramic media (in my case) every so often. I think the newer JBL filters have one ceramic layer and two foam layers, but you can just replace the foam with ceramic media. I only used half the ceramic media supplied in each tray so as to not impede the flow too much. Works fine.

The supplied hoses are dark and are supposed to not clog as don't let light in, but eventually I cleaned mine (and inline diffuser) after about 4 years and did have a lot of gunk in them.


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## Twisted Melon (14 Feb 2018)

Perfect Ian. I hadn’t considered running costs until now. And that looks pretty easy to maintain so ticks all the boxes. 

Ta.


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## Twisted Melon (14 Feb 2018)

ian_m said:


> If you are going to use two filters with handy standard sized tubing eg JBLe1501 with 16/22mm tubing, then you plumb it as below. Main points are two sections of spray bar and two needle valves to control CO2 rate to each filter. Connecting two filter inputs or outputs into one pipe is a big no-no, you must have seperate piping.



I see you’ve got the diffusers on the outlets there. I see a lot of people also put them on the inlet so the filter acts as a reactor. I take it I can just do that mid to this setup also?

Cheers


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## ian_m (14 Feb 2018)

My JBLe1501 was chosen as it is the biggest filter I could get in my cabinet without having to perform extreme carpentry.


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## ian_m (14 Feb 2018)

Twisted Melon said:


> I see you’ve got the diffusers on the outlets there. I see a lot of people also put them on the inlet so the filter acts as a reactor. I take it I can just do that mid to this setup also?


Don't see why not some people have no issues with diffusers on the inlets.

However there are downside.

Being on the dirty water side the diffuser blocks quickly and will need more frequent cleaning. My diffuser went for 4 years on outlet, with no issues, before I cleaned it. Probably smaller bubbles once cleaned.
CO2 can get trapped in the filter and cause noise, burping and other trapped gas issues.
CO2 will dissolve in rubber making it hard and crackable or soft and runny. So need to watch out on filter seals.


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## Twisted Melon (15 Feb 2018)

Just looking at your diagram again. Can the CO2 not jus be fed into one filter to save the cost of another needle valve etc?


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## Twisted Melon (15 Feb 2018)

Or, use a T piece to split the CO2 feed after the single needle valve?


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## ian_m (15 Feb 2018)

Twisted Melon said:


> Just looking at your diagram again. Can the CO2 not jus be fed into one filter to save the cost of another needle valve etc?


No as you will not be getting decent CO2 distribution on the other side of the tank. People have done this and suffer CO2 issues on the non injected side. Getting correct CO2 levels & distribution right is hard and is one area many many people get wrong and blame water, plant quality, lack of ferts, too little light, colour of their underwear, its Tuesday, where as in fact it is their CO2 levels and distribution at issue.



Twisted Melon said:


> Or, use a T piece to split the CO2 feed after the single needle valve?


No, won't work, you must have two needle valves and two bubble counters. If you just have one needle valve with a splitter, you will find the CO2 will take the path of least resistance and only diffuse via one diffuser, which is why I drew two needle valves in my drawing. Hey, but keeping a large (beyond 200l ?) planted tank would never be cheap or easy.

I have only drawn one heater in my diagram and many people have done this and works fine, unlike CO2 from one filter only. I suspect it is because the heat transfer time to other half of tank may be many many hours to get even temperature, but this doesn't matter in the scheme of things, unlike CO2.

Some people use two in line heaters, just to act as redundancy. See Zues's 500l tank, I think he has two heaters.


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## Edvet (15 Feb 2018)

ian_m said:


> colour of their underwear


Go "commando" i'd say


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## Twisted Melon (15 Feb 2018)

Do you get lower watt heaters if you have 2?


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## ian_m (15 Feb 2018)

Twisted Melon said:


> Do you get lower watt heaters if you have 2?


Yes Hydor do 200W in 12mm & 16mm and 300W in 16mm.

http://www.hydor.com/eng/prodotti-tecnici/heaters/heater-for-external-canister-filters.php


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## Zeus. (15 Feb 2018)

Twisted Melon said:


> Do you get lower watt heaters if you have 2?



Shouldn't matter having too powerful heaters as long as the heaters thermasat doesnt get stuck in the on position- which can happen. So geting lower power ones has its advantages


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