You don't have to have a 4 dkh to inject. I have a buddy running straight rodi water in his tank with discus with no dead fish. I have a kid so I had a old baby food jar already, but who doesn't know someone who doesn't have a kid they could get a jar from for free. Funnels are $2 at wal-mart $4 for a tube of silicon, $1 to get a gal of distilled water and bow of baking soda, $1 for a suction cup. Ph test solution anyone should already have that owns a fish tank. A total cost of $8 and 10 min to put it together and have enough stuff to make 3-4 drop checkers. The solution you make for $1 is free of anything that will mess up your co2 test. Buying a co2 test online they don't come with the 4 dkh solution which makes it just as good as dropping your ph by 1, cause you have all kinds of stuff in your tank that mess with ph like wood, peat, ect.
Measuring CO2
- Thread starter NewObsession
- Start date
Noooooooooooooooooo! While any tanks should have *some* buffering capacity, pH drop due to CO2 addition is normal & harmless. Adding buffers to tanks is a good way to induce stress at PWC time, unless you're into matching your replacement water's GH w/ what's in there.
Tank pH & hardness have NOTHING to do w/ dropchecker function. The solution in the dropchecker (which never touches tank water, unless something goes wrong) absorbs CO2 from the tank water via the air gap between them. *IF* the solution in the dropchecker contains 4dKH & a few drops of indicator (bromothymol blue, very dilute, available in your API test kit), it will go from blue to green at ~15ppm and from green to yellow a bit above 30ppm CO2. It doesn't matter if your tank's KH or GH are 2, 20 or anything in between. Higher KH in the chesker - higher CO2 concentrations to make color changes, lower KH -->lower CO2 levels to change colors...
PS - Discus in RO/DI - not a good idea (literally 0 buffering capacity, severe osmotic pressure issues...)!
PSS - making 4dKH is a bit tricky due to 1) moisture in baking soda 2) nasty habit of bicarb converting to carbonate if you heat it to deal w/ moisture. To do it right, you need a very accurate balance, a moisture meter (KF type, preferably) and volumetric glassware.
My baby food jar drop checker cost me under a dollar since the only thing I had to buy is the distilled water. But if you dont already have most of the materials I agree they are cheap just to buy and pretty decent looking. I might opt in the future though to buy the reference fluid, it was a PITA to make mine and now with the first refill of my DC it looks like the fluid has gone bad somehow :mad2:.
you may have a contamination issue - the reverse funnel type has one design flaw... you can't effectively empty it when you go to rinse out the old stuff!
Also - the dye lasts longer if the DC is kept low +/or in a major shadow - it's light sensitive.
Also - the dye lasts longer if the DC is kept low +/or in a major shadow - it's light sensitive.
My 'reverse funnel' doesnt have that issue since I'm using a baby jar I can take the lid off to completely clean it, one reason I did it that way. For example take a look at this pic with the lid off:
I fixed one flaw since I took the pictures though... the base of the baby food jar isnt flat, and when upside down the lowest point is the middle. Might not be a problem for those that keep it out of light and all but I noticed mine had some condensation. And my water level kept going down slowly. I surmised that the condensation was dripping from the center of the top down through the funnel into the tank. So I trimmed the funnel a little shorter (it was too long when I initially did it) and with the cut off piece I cut it in half making a kind of tent shape wich I placed over the top of the funnel opening, like the cover of a chimneny to keep stuff from getting down it.
The problem I had with the 4* KH solution I made was that when I went to refill it instead of turning blue right away it turned green right away. I had it stored in a cleaned out glass jar that was originally salsa. I could smell a hint of salsa in it so maybe it just wasnt 100% clean. IDK, but I'll throw it out and either make some more or just purchase some online.
OK, Now I have a question..
I bought a drop checker from that fish place dot com.
the instructions said add 1ML tank water to the jar, and add 2 drops of solution provided with the kit. Never says anything about the KH of the blued water. How do I know it is 4KH? I never really tested the tank water KH before I added the drop checker and co2.
is the drop checker going to be accurate now? its still blue, I am runing about 40 bubbles a minute into a 125 gal tank.
I bought a drop checker from that fish place dot com.
the instructions said add 1ML tank water to the jar, and add 2 drops of solution provided with the kit. Never says anything about the KH of the blued water. How do I know it is 4KH? I never really tested the tank water KH before I added the drop checker and co2.
is the drop checker going to be accurate now? its still blue, I am runing about 40 bubbles a minute into a 125 gal tank.
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Zig - I have actually never seen a drop checker that came with correct fluid or instructions except for those built and sold by forum members. Unless you know for sure, I'd toss it (the fluid that is) all it needs to be is distilled water, baking soda, and blue pH indicator fluid (bromothyl blue). The hard part is getting the KH accurate, you want at least .5 accuracy and it only takes like a pinch for a whole gallon of water it seems.
Just FYI 40bpm is really nothing in a 125... I'd expect you will end up needing closer to 10-20X that much. My 75g runs about 4 bubbles/sec, and my high flowing 240g is probably nearer 40bps, but the controller does turn it off every so often.
Just FYI 40bpm is really nothing in a 125... I'd expect you will end up needing closer to 10-20X that much. My 75g runs about 4 bubbles/sec, and my high flowing 240g is probably nearer 40bps, but the controller does turn it off every so often.
tested the kh of my tank water... 6dkh it was 11dgh. I tested the tap water, one drop turned the vial blue (API kh test solution) Anyway whenever I create some 4dkh, how much blue solution do I put in it?
