Need some chemistry clarifications from the pros here
Posted: Fri Jan 29, 2016 8:39 am
Hi!
I have this setup home:
FACTS:
The water starts in a 40l reservoir, and drips through expanded clay pellets medium, before running back to the reservoir. the driprate is pretty low, and the pump turns on for 30min, and off for an hour - 24/7. The lights are on 18/6.
An airstone in the reservoir is on 24/7 for removing CO2 and adding DO.
I use tapwater, which is basically rainwater here in Oslo. It has very little chemicals, and are pretty soft. (PH 7, KH 2)
The batch I have now, has 50ml per 10l of nutrients.
I've also added some aquarium KH+ to try to achieve a more stable PH. (My PH was decreasing all the time before)
PROBLEM:
The PH is raising high every day. It goes up to as high as 9+. I use phosphoric acid to lower it back to 6,5.
24h after, it's raised back up again.
QUESTIONS:
1. I've read that when plants thrive, they eat more nutrients than water, which causes the EC to go down, and the PH to rise. But will this phenomenon make the water even more alkaline than it was when I tapped it?
2. I don't have an EC meter. Could a Nitrate test for aquariums be a better solution to measure nutrients?
3. I've read that algae can rise PH, and that this can be treated with H2O2. Will H2O2 also affect the bacterias that turns ammonia into Nitrite and Nitrate? This concerns me as I'm eager to move over to aquaponics when I feel I got more control.
4. KH works as a buffer for PH. Does this mean that when I add KH, and then adjust the PH with phosphoric acid or potassium hydroxide - my PH will be more stable, or am I "using up" the KH by lowering the PH?
5. Can my airstone remove enough CO2 that my PH increases significantly? And how long time will it take before an reservoir @ 40l is in DO equilibrium with a single airstone? Are we talking hours, days?
6. When I use phosphoric acid to lowering the PH - will this remove some of the nitrates? If so, which of them, and would it be significant?
7. I've read that you can build a buffer using either a strong acid
and weak base, or a weak acid and a strong base. Is this a way to "lock" the PH? and would it be harmful to the plants if I use too much of these chemicals?
8. Could an unbalanced ammonie/nitrite/nitrate cyclus be affecting the PH?
I hope you have some clever answers for me =) Thanks a lot!
I have this setup home:
FACTS:
The water starts in a 40l reservoir, and drips through expanded clay pellets medium, before running back to the reservoir. the driprate is pretty low, and the pump turns on for 30min, and off for an hour - 24/7. The lights are on 18/6.
An airstone in the reservoir is on 24/7 for removing CO2 and adding DO.
I use tapwater, which is basically rainwater here in Oslo. It has very little chemicals, and are pretty soft. (PH 7, KH 2)
The batch I have now, has 50ml per 10l of nutrients.
I've also added some aquarium KH+ to try to achieve a more stable PH. (My PH was decreasing all the time before)
PROBLEM:
The PH is raising high every day. It goes up to as high as 9+. I use phosphoric acid to lower it back to 6,5.
24h after, it's raised back up again.
QUESTIONS:
1. I've read that when plants thrive, they eat more nutrients than water, which causes the EC to go down, and the PH to rise. But will this phenomenon make the water even more alkaline than it was when I tapped it?
2. I don't have an EC meter. Could a Nitrate test for aquariums be a better solution to measure nutrients?
3. I've read that algae can rise PH, and that this can be treated with H2O2. Will H2O2 also affect the bacterias that turns ammonia into Nitrite and Nitrate? This concerns me as I'm eager to move over to aquaponics when I feel I got more control.
4. KH works as a buffer for PH. Does this mean that when I add KH, and then adjust the PH with phosphoric acid or potassium hydroxide - my PH will be more stable, or am I "using up" the KH by lowering the PH?
5. Can my airstone remove enough CO2 that my PH increases significantly? And how long time will it take before an reservoir @ 40l is in DO equilibrium with a single airstone? Are we talking hours, days?
6. When I use phosphoric acid to lowering the PH - will this remove some of the nitrates? If so, which of them, and would it be significant?
7. I've read that you can build a buffer using either a strong acid
and weak base, or a weak acid and a strong base. Is this a way to "lock" the PH? and would it be harmful to the plants if I use too much of these chemicals?
8. Could an unbalanced ammonie/nitrite/nitrate cyclus be affecting the PH?
I hope you have some clever answers for me =) Thanks a lot!