New to this website, and to keeping fish, I have a 100gal, no live plants, I've learned about cycling the hard way and have done a lot of research on fish keeping lately. My Ammo is 0, Nitrite is 0, Nitrates are 20, I'm having a problem with two things, PH and, from reading a post in this website, Diatoms. After a 50% water change the PH is 6.8 to 7.0. Then in about a day or so, PH starts droping quickly. Third day or fourth is 6.0 or lower. How can I keep the PH at around 7.0? and what do I do about the diatoms? Any help would be appreciated. I got this aquarium for my wife for Christmas, I told her it was good for her stress, that didn't work out too good, she loves her fish and I have to do all I can to keep them all happy. Thanks,,,,....
Algae issues
- Thread starter rliverett
- Start date
The friendliest place on the web for anyone with an interest in aquariums or fish keeping!
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
Jchillin
Aquarium Advice Addict
I split your topic from the thread you had posted in rliverett. What is your source water? You need to find out what your kh is. This will let you know if you have sufficient buffering in your source water. As far as the diatoms are concerned, they are very common and usually go away on their own in time.
Source water is city water, always checks PH at 7.0. Dont have test for KH, guess I'll have to get one now. Funny thing, during cycling a few months ago, PH seemed to be the only thing that stayed at 7.0. Dont know what's changed. I'll go get a test for hardness and do some research on "buffering". Thanks for the advice.
Dropping pH is strange. If it's rising an easy cause is rocks (limestone, and limestone based rocks such as marble).
Is there driftwood in the tank? Tannic acid will drop the pH. It could be be organic acids in the water I suppose, but that's a bit strange.
Is there driftwood in the tank? Tannic acid will drop the pH. It could be be organic acids in the water I suppose, but that's a bit strange.
PH dropping
No driftwood, just store bought items specifically for aquarium, three fake rocks and several plastic plants. Bottom is cleaned and boiled river rock, bought at the store too. Just did 50% water change last night, PH is at 6.8 now, but going on past results, it will drop by tonight just slightly and continue to drop?? The only thing I added was some aquarium salt. About two months ago, we had ICK, it was reccommended that I add salt to the tank to aid in the cure. I added only half of what was suggested, just enough to treat 50gal of the 100gal in the tank, I know these are not salt water fish and believe in trying to NOT use additives. That and raising the temperature to 82 deg. killed the ICK. But subsequent water changes should have rid the salt by now. Does salt affect the PH? Perhaps it will stabilize, but we do water changes once a week of 25% and once a month at 50%. I would think that two months of that would completely change out all the water in the tank in time. I guess I need to do more research specifically on PH and look at what can cause change and what on that list I am doing wrong??????
No driftwood, just store bought items specifically for aquarium, three fake rocks and several plastic plants. Bottom is cleaned and boiled river rock, bought at the store too. Just did 50% water change last night, PH is at 6.8 now, but going on past results, it will drop by tonight just slightly and continue to drop?? The only thing I added was some aquarium salt. About two months ago, we had ICK, it was reccommended that I add salt to the tank to aid in the cure. I added only half of what was suggested, just enough to treat 50gal of the 100gal in the tank, I know these are not salt water fish and believe in trying to NOT use additives. That and raising the temperature to 82 deg. killed the ICK. But subsequent water changes should have rid the salt by now. Does salt affect the PH? Perhaps it will stabilize, but we do water changes once a week of 25% and once a month at 50%. I would think that two months of that would completely change out all the water in the tank in time. I guess I need to do more research specifically on PH and look at what can cause change and what on that list I am doing wrong??????
jsoong
Aquarium Advice Addict
If your tap pH is 7.0, I would hazzard a guess that your KH is near 0. (Assuming that you have no other buffer (like phosphate in the water), then I can calculate your KH assuming atmospheric CO2.) However, to be sure, you really should test for KH. (Alternatively, many water co. post the water quality result on the net, there is usually a KH reading, or more likely, TDS (total dissolved solids) or HCO3 concentration.)
Your unstable pH is most likely a reason of low KH (& buffering capacity). The nitrification process (ie the cycle) produces acids (ie NH3+ -> NO3-- + H+), and if there is not enough buffers in the water, will cause a pH crash.
The simplest way to increase buffering capacity is to add some crush coral (or shells, or limestones or CaCO3) to the tank. This will gradually dissolve & raise the KH (and pH), & prevent future crashes. This is the only water doctoring recommended for a FW setup. I would suggest, however, that you be sure of the KH level before adding anything.
BTW, salt will lower pH, but not at the levels you are at. 0.9% NaCl (ie full marine) has a pH of around 6.0. However, with buffers in the water, the drop in pH is much reduced.
Your unstable pH is most likely a reason of low KH (& buffering capacity). The nitrification process (ie the cycle) produces acids (ie NH3+ -> NO3-- + H+), and if there is not enough buffers in the water, will cause a pH crash.
The simplest way to increase buffering capacity is to add some crush coral (or shells, or limestones or CaCO3) to the tank. This will gradually dissolve & raise the KH (and pH), & prevent future crashes. This is the only water doctoring recommended for a FW setup. I would suggest, however, that you be sure of the KH level before adding anything.
BTW, salt will lower pH, but not at the levels you are at. 0.9% NaCl (ie full marine) has a pH of around 6.0. However, with buffers in the water, the drop in pH is much reduced.
Similar threads
