Aqua Man
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I could possibly attribute. The ph difference between tap and RO with only nutrients to evaporation. Ph will drop ass ppm increases this effect will be less pronounced in tap because it's more alkaline.I was describing what I noticed just with tap water and ro water in separate buckets, no plants, no nutes, no ph adjustments, no other variables. I tested this because I found when I was using the ro water (specifically early in veg) the ph would slightly drop over time from where I had adjusted it and with tap water it either stayed the same or slightly rose. After some research just now I think I found some relevant info:
"Because reverse osmosis removes the minerals in water the water will then react with carbon dioxide upon exposure to air to form carbolic acids, thus lowering the pH. The resultant pH will depend on the initial water chemistry. It cannot be predicted. "
and more technical
"When water is passed through a semi permeable membrane using pressure, many organic and inorganic compounds fail to pass through, however gases like Carbon Dioxide make it to the other side. CO2 combines with the free OH- ions in water to form acidic HCO3, while the H+ ions fail to find any substance to interact with as most of the impurities have been removed through the RO process.
CO2 + H2O <--> H+ + HCO3-
As a result, water has a positive balance of H+ ion, lowering its pH and making it acidic. (Again, remember, pH is measure of H+ with a minus. No more chemistry further, we promise!). The greater the amount of CO2 in your water, the greater is the drop in pH level"
Both are rising bust one keeps hitting the 7 mark and one the 6.8, I tried the Baking soda method yesterday, changed the res added baking soda, nutes, and ph down, one was ph'd to 5.8 the other to 6.1, today the 5.8 one was 6.5 ph, the 6.1 was around 7.2, I dont really know I'll take a picture of the rocks I'm using, I added some more baking soda and ph down and phd both to 5.8, gonna wait till tonight and re measure, the plants did grow tbh but I'm not liking the colours one bit, greenish yellow, they look healthy but the color is my issue, if it's the rocks, would it be possible to dig the sponge out and change out the rocks or would that no be good for the plant? Might as well do it now than later:/Easy to test and find out. While it can contribute I cant see it being responsible for a spike that big. I would say your ph is not stable but it could be contributing if that's the case. Are you finding this ph rise in both?
And if it is contributing I would stop using it.
So I have checked my ph again just now and it shot from 5.8 to 6.5:/ any ideas guys I'm starting to get frustrated
Can you take a picture of your ph down for me? label and ingredients.So I have checked my ph again just now and it shot from 5.8 to 6.5:/ any ideas guys I'm starting to get frustrated
I have used that exact method and order but no luck, I have increased the baking soda amount to see what would happen.Ok are you using tap water? Are you aerating it first?
I gave you small amounts to start with. Use tsp of baking soda. Then nutrients then ph down in that order ph last always or your ph will not be right.
Using tap water and no I am not aereating it first, I let it sit out for a bit and I dont use an air stone since the system is supposed to aerate the waterI have used that exact method and order but no luck, I have increased the baking soda amount to see what would happen.
Ok that could be part of the problem. So you may need to go back and re ph the water a few hrs after. Tap water is a closed system so carbonic acid in the system take a while to off gas CO2 and the ph will rise. You can either adjust ph after a couple hrs or aerate the water for a few hours before adding.I am
Using tap water and no I am not aereating it first, I let it sit out for a bit and I dont use an air stone since the system is supposed to aerate the water
Always a good idea to aerate water. It help the gas exchange so that balances the CO2 levels and all gasses for that matter between the air and water.I hope that helps, do you thing I should add an air stone to the reservoir if I can get the air tube through?
Sounds good I'll get to it and let you know how it goesAlways a good idea to aerate water. It help the gas exchange so that balances the CO2 levels and all gasses for that matter between the air and water.
A little off topic but since we are discussing improving the aquafarm by adding an airstone (I highly agree with doing this!) I would also recommend before you start you next grow drilling some larger holes in the bottom of the top part of the unit. You will know what I mean once this grow is done and you see how jam packed with roots those holes become.Sounds good I'll get to it and let you know how it goes
I actually thought about this seeing how small they are but didnt want to mess with the setup, I'll definitely do that once this is all done successfully I hope.A little off topic but since we are discussing improving the aquafarm by adding an airstone (I highly agree with doing this!) I would also recommend before you start you next grow drilling some larger holes in the bottom of the top part of the unit. You will know what I mean once this grow is done and you see how jam packed with roots those holes become.
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