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Finally some clear answer...i will put some co2 in my tank...because my HC doesn't grow well.Hope it will get better soon.
Hello..... I am setting up a 60p, 17 gallons tank... I have a 5 pound tank with CO2 regulator with AQUATEK 3-in-1 Diffuser with Bubble Counter and Check Valve.

How much oxygen do I need to diffuse in the tank ?

How do I keep track of the CO2 and how much is need it ?
You don't need to diffuse oxygen in the tank. It is produced by plants during the day. Strong surface agitation can help get more oxygen in the water at night, and it helps driving out surplus CO2 at nght.
Keeping track of CO2 is the hardest part. As you have read in this post the color of a dropchecker can give an indication (but just slow and depending on the reagents you use), a PH profile (how does the ph of your water measure when the CO2 is applied, take measurements every hour) gives a better indication, and the way the plants are gives an indication too.

My advise is to read all posts in the tutorial section thouroughly, this should clear up a lot of questions, and stear you toward the right questions to ask us:http://www.ukaps.org/forum/forums/tutorials.34/ It may seem a lot. but you can learn a lot there, do the groundwork and you will know better how to start!
add more CO2 gas slowly going down by 0.1 pH units per week till you see optimal new growth and fish and livestock are fine.
This is the tweaking stage.

You can adjust by eye only using a drop checker.This is more dicy for newbies and pros alike. I'd rather be able to measure it relative to the pH.
It may not be exact, but relative to a starting point, it's far more accurate than anything else we have to work with.

In several months, I'll have a device that addresses the issue and you can avoid the whole KH issue like the Drop checker does, but it'll respond in 60 seconds and will be accurate to about 1 ppm.

Should run about 50-100$ or so.

This is what i did with my Co2. Increasing just as T. Barr said.. and the fish get adapted.

What is this device he´s reffering?
Not sure where that was heading. I asked the same question a while back. There was a device made a while back which had a digital monitor but it only measured co2 levels, someone made one after people chipped in on one of those sites where people put money towards it and someone builds it. The last I heard they were in production for around 100 quid mark but people were struggling to get hold of one. I suspected Tom was also making a similar thing although I could be wrong. Either way I haven't heard anything about either in a long while so don't know if it fell flat or still in the pipeline.
This was the conversation I was referring to.
I've been using only that blue liquid in my drop checker, without any kH4 water or anything else. Does it still show correct results this way?
I've been using only that blue liquid in my drop checker, without any kH4 water or anything else. Does it still show correct results this way?

You need to find out if your DC fluid is pre-mixed 4dkh with Bromo blue ph indicator. If you are just using Bromo blue then no, it needs to be in a 4dkh solution to be working properly.
Hard to tell going off the description. It is suggesting adding aquarium water after the drops of fluid (Which is a bad idea as it will measure any acids in the aquarium water and give false readings) So I would say that you only have the ph indicator and not the 4dkh fluid. Also the ph indicator you need is bromo blue. I've came across some of these imported ph tests that used a different ph fluid.
Many thanks for a great read and basic information that’s was easy to understand for a newbie like myself into the planted game. One question I have is that it’s suggested to use 4dkh water in your drop checker. So where can I buy 4dkh water from besides eBay??? I spoke to a couple local fish shops and they thought I was talking a foreign language!
Hi all,
So where can I buy 4dkh water from besides eBay???
You can use bicarbonate of soda (NaHCO3), but you need to buy the bromothymol blue pH indicator. I haven't used them, but "kitchen-chemistry" on Ebay sell bromothymol blue pH indicator.
There is a recipe for it in the link from darrel
<"This one">.
I'd use 6g of NaHCO3 in 500cm3, which is a 400dKH stock solution. You can store the 400dKH solution in a stoppered bottle for as long as you like.

If you take 5cm3 of this stock (which I'd weigh as 5g) and make it up to 500cm3 (500g) with DI, you have a 4dKH solution, to which you add a drop of <"bromothymol blue">.
cheers Darrel
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