chewzas

Let me give you some information first. My tap water has pH 7.5, ammonia .25, nitrite and nitrate 0, alkalinity 40 mg/L and hardness 25 mg/L. Before my tank (20g) has cycled, ph was 7.5. After using "SafeStart" to help cycle my tank, the ph went down to 6.8. It took about 2 days to get my tank cycled. A week later, it droped to 6.4. And, now it's 6.0. I use API liquid test kit and test the water almost every day. I do a 25% water change every week. I also add aquarium salt into the water. My current reading on the water is ammonia and nitrite 0, and nitrate 10.

Should I use coral sand to raise the ph buffer. Or shold I just leave it there? I'm worried that my actual ph might be below 6.0 because the lowest ph value on the chart is 6.0.

I have 4 neons, 3 mollies, 1 balloon molly and 2 marigolds.

I was crazy when I started to cycly my tank with fish. (next time, I will do fishless cycle.) Now, ph is killing me and my fish.

Any help would be greatly appreciated.

Chew

clinton1621

A pH below 6 is not very likely... it should stabilize before it gets that low. Do you have real driftwood or live plants in the tank?

chewzas

Thanks for quick response, Clinton. I hope that the ph isn't below 6.0, too. I don't have any those in the tank. I just have a few ornaments and plastic plants.

Is it because my tank is overstocked? Too much phenol? But nitrate has always been 10 since it's cycled.

clinton1621

I'm not familiar with phenol... I know its an acid, but why would that be in your water? Are you using peat in the filter?

chewzas

You're right. Phenol is an acid. I read from a book. It says that phenol is a by-product of amino acid and amine during the mineralizing stage. This is done by beneficial bacteria right after nitrogenous waste is produced by fish, and it occurs before the nifrification stage. Then, amino acid is converted into ammonia/ammonium.

I don't use peat because it will reduce hardness and ph, isn't it? Actually, I want to keep my ph level about 7-7.5 because it's best for mollies.

The reference book is "The Complete Book of the Freshwater Aquarium," written by Vincent B. Hargreaves. It's a good comprehensive book. I would recommend it.

clinton1621

Very interesting, I knew that pH decreased with higher waste levels, but I didnt know the exact reason. And yes peat does release acids... I believe phenol is one of them (I googled it lol), and its main use is to lower pH. It seems like we have ruled out pretty much everything other than stocking levels, which dont look overly bad... I would say that you probably have soft water. If you want to confirm this then you need a test kit for GH and KH levels in your water, but I would be willing to bet thats probably the root of your problem and the fish load is just making the pH drop faster. I would try adding some spring water, the gallon jugs from the store, change about 10 gallons out with the spring water as a replacement and see if the pH goes back up. The springwater usually has a moderate hardness content, you can also use crushed coral in the filter... but the coral may make the water overly hard and you will end up with a pH range in the 8's.

Edit : You probably already know this, but regular gravel vacs will also help keep the ph stable by reducing the amount of waste in the tank... also higher oxygen levels help keep the ph up (dissolved co2 lowers pH)

clinton1621

Nevermind about the GH and KH test, I see your readings in your intial post... a GH of 25 is definitely soft water, you need the GH reading to be closer to like 150 for a steady pH in the 7's... the KH should be around 150 as well. I would definitely use the spring water that I mentioned above if you want to be in the 7's, or else your pH is going to remain in the 6's due to the softness of your tapwater.

I use spring water myself because my tapwater has a GH and KH of about 300 for both (which is way too high for what I want) and the spring water has a GH and KH usually close to 150 for both... although I dilute that even further with distilled water because I like a ph around 6.8 to 7, buts thats just me lol.

To give you an idea of how soft your water is... my diluted spring water setup usually gives me a steady 6.8 to 7 pH... and my GH and KH are both around 120. Compare that to your 25 GH and 40 KH, and my pH would be about 5 or less (I have driftwood)

chewzas

Thanks a lot for your recommendation, Clinton. I will try to use spring water to increase KH and GH. I also might add some crushed coral. I hope it would work. I'll keep you update.

I agree with you about the regular vacumm. Now I do it twice a week. I also reduce the feeding.

It's so sad that my tapwater is so soft. I didn't know about this before I started my aquarium, otherwise I would go for some fish that like softwater and low ph.

Butterfly

What are you using to test with? (I'm sorry if I missed it in your post)
Carol

clinton1621

No thanks necessary =)

I wouldnt overdo the gravel cleaning, once a week max is good... otherwise you are disturbing the bacteria thats established in the gravel too much.

Your tapwater would be perfect for Discus and Angels lol

chewzas

I use API test kit for ph, ammonia, nitrite and nitrate. For GH and KH, I had PetSmart test them for me. Maybe I should get a test kit for GH and KH for myself.

Carol, do you know about a test kit that can measure ph below 6? If the ph in my tank is stable at 6.0, should I leave it there? A lot of people say that we shouldn't mess with the ph. And, I think that my fish don't require higher ph level to survive.

Jess

I agree, Discus would love your water.
Sometimes its better not to fight with what you have and work with what you got.
My water is neutral but goes soft with wood and peat.

clinton1621

I would get your own test kit, but with the constantly dropping pH, I would say it was right. And yes fish can survive in most pH levels just fine... but if your GH and KH are too low (yours are) then the pH is not going to be stable, which is bad. You need to have a decent GH and KH level to keep the water stable, it also helps the fish because they use the minerals from the water... again if its too low then the fish will suffer.

Jess

Ummm Clinton you just made your 666 post. Remember the movie Damien? Scary stuff.

clinton1621

LOL, I noticed that too, right after I posted

Butterfly

Excellent test kit
The only thing I've seen measure PH below 6 is a PH meter. They are cheaper if you buy one from a wine making supply than if you buy them for an aquarium. But essentially the same meter.

I honestly wouldn't tamper with the water too much unless you are really losing fish or you want to keep something that is really sensitive to PH. When you start adding stuff it's really tough to get the water the same at each water change. Most fish will be happier and healthier in a stable Ph than the fluctuations we cause trying to make it "perfect"
Carol

chewzas

You guys are right. I should have gone for discus and other softwater fish. Unfortunately, I didn't know about water chemistry before I started my tank. So, I guess I have to deal with what I have now.

I added crushed coral this morning to increase the hardness. I hope it will bring the ph up a little bit. The recommended amount of crushed coral is 1kg for 40 liters of water to hold a ph around 7.6. I'm also going to buy GH&KH test kit and springwater, just in case that the crushed coral doesn't work.

chewzas

Maybe you watch the movie too much.

chewzas

I totally agree with you, Carol. But, as Clinton said, I think my water is not really stable because of very soft water. I hope that the crushed coral that I added would help a bit.

Although I didn't lose any fish, IMO some of them are showing stress like hiding and staying still. I hope my fish survive during this period.

chewzas

Here is the result from day 1 after using the crushed coral. I put it in my tank this morning. I just tested the water and the ph was 6.4. I couldn't test the GH and KH because there was no liguid test kit for GH and KH at either PetSmart or LFS. They have only GH/KH test stripes but I don't think they are accurate. I'll wait to test the water again tomorrow. Right now, I just leave it like that. 6.4 is good enough for me.

clinton1621

The strips are good enough for a rough guess on GH and KH, they are not precise to the exact number... but you really dont need to be precise since its more of a range that you are looking for and not an exact number.

Jess

No way, I'm the biggest baby. Think I had my eyes covered! But I have a great imagination.

chewzas

I have an update on my ph issue. Finally, I could get an API KH&GH test kit (liquid) from a LFS. I've just tested the water from both the tapwater and the tank. The result was quite confusing.

Tapwater: PH 7.5, GH & KH 35.8 PPM
Tank: PH 6.8, GH 53.7, KH 35.8

I thought that adding crushed coral would increase ph buffer or KH (Carbonate hardness). If the KH hasn't increased, dose it mean that increasing ph from 6.0 to 6.8 was because of the increase in GH?

Does anyone has any idea about this? I think I might miss something here.

Note: From the date I found out about the very low PH of 6.0 in my tank (4 days ago), I haven't done anything to the tank except adding the crused coral. Just try to give you information as much as possible.

clinton1621

GH is the total hardness of the water... KH is the alkalinity... so you are raising the waters hardness by adding calcium (the dissolving coral). Alkalinity is a little more tricky... its more about the ion content of the water and not the actual hardness. Alkalinity determines how well your water can 'hold' a pH level, for example... water with a gH of 300 and and a KH of 30 (not a very likely scenario by the way) would have a low pH even though the water is hard. Thats because the Alkalinity of the water can not 'hold' the pH up to match the hardness of the water.

So yes... raising your GH will allow your pH to rise, but the KH is the limiting factor in how high the pH can actually go. Also crushed coral takes a long time to dissolve... so you're not going to see any immediate large increases in KH, it will raise the GH first and the KH should slowly catch up. Thats why I recommended using spring water... it already usually has a good KH and GH range.

pepetj

chewzas: Tetra used to have a pH liquid reagent test that measures in increments of 0.5, I believe from 4.5 to 10.5 (still available in Santo Domingo, but I haven't found it in the web, so it's probably out of market; I didn't purchase one since I wanted a more restricted range and it's intended for both saltwater and freshwater, which made me suspicious of it's reliability). A digital meter would do the trick. Although a bit expensive.

Your pH could actually be below 6.0, as API literature clearly states. You barely have dissolved minerals in your water (3 dGH) and your dissolved carbonates are below 2 (1.4dKH), that if your readings are accurate for alkalinity and hardness; if Petco used strip test for that, don't trust those results.

There's some disagreement for what the safe lower limit for DKH is: either 2, 2.5, or 3.0 depending on the sources. Below that -I use 2.5 as reference- pH swings or even worse, a pH crash, could easily happen, and no life-stock would survive it.

I know it's not a good idea to tamper with pH, but, in my honest opinion, you do need to raise your alkalinity and hardness a bit. If mixing spring water doesn't help, and I believe it should solve your problem, adding baking soda (e.g. Arm & Hammer) in proper dosage would do the trick. The active ingredient in baking soda is what makes crushed corals raise pH, as far as I know, double-check this info before going for it. I'm suggesting this solution due to the likelihood of a pH crash happening in your tank.

To do this safely, add slowly and keep measuring, err on the lower side, since it's always easier to raise pH than to bring it down. If you had no fish you would have more margin of error, but since you are already stocked, then be very, very, careful.

Keep in mind that measuring pH from our source water requires us to let the water sit in a shallow plate overnight and measure next morning, in order to obtain accurate readings, this is so because either transient dissolved CO2 or O2 levels -due to water agitation as it travels through the pipes, pressurized water pump, hose, etc. could/would provide errors of measurement (usually in the range of 0.5) easily.

I would love to have your soft water down here! It's great for most South/Central American Cichlids.

Pepe
Santo Domingo

clinton1621

Actually baking soda mainly increases KH, and not GH... baking soda is an alkalinity buffer, in other words it raises the waters ability to hold a desired pH level but it doesnt add enough minerals to actually bring the GH up to acquire a higher pH level. Using baking soda to raise your pH is basically like using an acid to lower your pH... you will end up with pH swings, but opposite of an acidic swing. Your pH will rise temporarily and then go back down... which isnt good... limestone and crushed coral are about the only safe way to "harden" soft water, this is because they raise the GH initially and the KH slowly rises with it. In short, you cannot alter your pH and make it stable without changing both the GH and KH levels... they are all connected in an equilibrium.

chewzas

Pepetj, I couldn't find any test that can measure ph below 6. I haven't tried on the internet though. But right now, ph in my tank has increased to 7.2 so I guess I don't need that ph test for now. Actually, I started to worry about the increasing ph. It has gone up from 6.0 (I believe) to 7.2 within 3 days. Here is the test result from this morning.

My tank: Ph 7.2, KH 2 dKH or 35.8 ppm, GH 3 dKH or 53.7 ppm

It seems that GH has increased a little bit after I added the crushed coral, but KH has remained the same. Although GH is the same as yesterday, ph has increased from 6.8 to 7.2. Isn't it kind of wierd? I thought that ph would go up together with GH. Maybe it's because of super low ph buffer so ph swings.

At PetSmart they used test stripes to test my water. But my test confirmed it that my tapwater is very soft.

Note: Still I haven't done anything else to the tank.

chewzas

Clinton, I have read about baking soda too. But I don't really understand how it works, so I'll wait a bit.

I tested the spring water I bought from Walmart, and the result is ph 6.4, GH 2 dKH (35.8 ppm) and KH 2 dKH (53.7). Super soft as well. I might try to get API proper PH 7.5 to increase ph buffer. I'm not sure if that's a good idea. Maybe I should wait a little longer and let the crushed coral does the work.

My fish seem fine. They swim and eat normally, except one marigold that most of the time hides behind the ornament and swims with its mouth up and is being nibbled by the balloon molly.

chewzas

Agree. I should have gone for South American Cichilds from the start. Unfortunately, I didn't know anything about GH & KH when I started my aquarium.

clinton1621

The pH buffer that you buy is actually about the same thing as baking soda... are you sure you bought (mineral) spring water? That test result sounds more like distilled water. At any rate, it actually looks like your pH is stablizing at a good level... so I would just stick with the crushed coral, add spring water instead of your tap water and call it good enough.