New tank, sudden drop in PH?

FishyFish · Feb 3, 2019

Hello, I'm very new to the hobby and not really sure how serious this issue is so please forgive me if I'm posting in the wrong place.

I have a brand new 30 gallon tank, it had been cycling for about a month and I just got my first fish (a pair of clowns) three days ago. There are no other fish inverts or corals in the tank but it does have about 20 lbs of live rock. My PH was steady at 8.0 the whole month I was cycling and went up to 8.2 as the cycle finished. My LFS also tested my PH at 8.2 the day I bought the fish so I'm sure that number is accurate. I was going to do my first water change tonight and all of my parameters are about the same as they were before the fish were added, except my PH has taken a sudden drop down to around 7.6. I checked it three times and got the same result each time.

I'm freaking out right now, is it normal for a PH to take a dive like this after adding fish? I have some PH stabilizer, should I add some of that or just wait and keep testing? Will proceeding with the water change maybe help or should I hold off on that until I figure this out? The fish seem to be okay, they're not very active right now but that may be because it's late and the lights are off, they were swimming around and eating well just a few hours ago. Here are the rest of my parameters, any help would be really appreciated!!

PH: 7.6
Ammonia: .25
Nitrite: 0
Nitrate: 30
Salinity: 1.023
Temp: 79.2

tupes · Feb 3, 2019

If that is your parameters you are NOT finished cycling

You should have 0 ammonia.. did your LFS test everything for you?

If you know, what test kits are you/they using?

Katrina71 · Feb 3, 2019

Agreed. No ammonia should be present.

TheEngineer · Feb 3, 2019

Welcome to R2R!

Agreed, you are not finished cycling. The presence of ammonia is the indicator here.

That said, there are natural daily fluctuations in pH. We aim for stability here rather than a hard number. Ideally you will be between 8.0 and 8.3 but as low as 7.8 is ok. There are a lot of things that will drive your pH lower.

One of those drivers is CO2 in the air. Do you live somewhere cold? Keeping the windows closed and the heat on will drive up indoor CO2. Especially in light of the polar vortex this could be more pronounced.

Liron Mishal · Feb 3, 2019

I think that before you attend to the low ph, you need to take care of your fish first.
I would dose some ammonia binder such as Prime or AmoGuard in order to neutralize the harmful ammonia.
I would also dose with some bottled bacteria.. I know it may not do any good but it would not do any harm as well
ammonia is toxic to fish, please take care of it asap. (WC would help too to dilute it)

Captain Quint · Feb 3, 2019

All solid info and all I can add is a warm welcome to R2R.

Several already helping on this awesome forum you have chosen.

jsker · Feb 3, 2019

FishyFish said:
PH: 7.6
Ammonia: .25
Nitrite: 0
Nitrate: 30
Salinity: 1.023
Temp: 79.2

Depending were you live and the house is closed up, them might be a fresh air issue.

Bring your salinity up to 1.025 and the PH will come up a bit.

Besides the testing above test Ca, Mg, Alk. Low Alk will make the PH drop.

What test kit are you using to test the PH?

FishyFish · Feb 3, 2019

Thanks everyone for the replies! I just rechecked the PH this morning and it's gone up to around 7.8

My LFS did test everything, they were using some test strips I'm not sure what brand they used but I'm using API's saltwater test kit. My water was actually tested by two different employees there on two different days and okayed both times just the first day they said my salinity was too high so I came back the next day after lowering it. Really disappointed to find out I should have kept waiting. They didn't say exactly what they tested my ammonia at, only that it was 'good'. I thought that the spike might just have been because the fish were just added or because I fed them a little too much. One of them decided that he didn't like the food I had ready so I had to try a few different types of food until I found something he would eat. I probably ended up putting in too much food in the process especially with no inverts in the tank yet.

I live in Texas so it's not super cold but the tank is in a fairly small room with the heater on and the windows are never open. Maybe the Co2 is my problem, any advice on what I can do to help with that? I read somewhere that adding an airstone could help but then I've also read that they don't do much in saltwater tanks.

Fortunately I do have some ammonia detox and PH stabilizer as well as some bottled bacteria handy. I will proceed with the water change right away and dose the ammonia detox and bacteria after that. Should I add the PH stabilizer too? It sounds like I won't need to, you guys seem much less worried about it than I was!! Thanks again for the help I really appreciate all of the quick replies.

tupes · Feb 3, 2019

Im sorry but using test strips is the first problem and using API is your second.

Not sure what brand of bottled bacteria that you have but you can just dump it in the tank. I used BioSpira with good results during my cycle.

tupes · Feb 3, 2019

No dont add nothing else but the bottled bacteria. Adding too many things at once can really throw off your system

Invest in some good test kits.

You dont need them all at first but you at minimum have phosphate nitrate nitrite ammonia on hand.

Salifert is a good brand to start with.

Captain Quint · Feb 3, 2019

FishyFish said:
Thanks everyone for the replies! I just rechecked the PH this morning and it's gone up to around 7.8

My LFS did test everything, they were using some test strips I'm not sure what brand they used but I'm using API's saltwater test kit. My water was actually tested by two different employees there on two different days and okayed both times just the first day they said my salinity was too high so I came back the next day after lowering it. Really disappointed to find out I should have kept waiting. They didn't say exactly what they tested my ammonia at, only that it was 'good'. I thought that the spike might just have been because the fish were just added or because I fed them a little too much. One of them decided that he didn't like the food I had ready so I had to try a few different types of food until I found something he would eat. I probably ended up putting in too much food in the process especially with no inverts in the tank yet.

I live in Texas so it's not super cold but the tank is in a fairly small room with the heater on and the windows are never open. Maybe the Co2 is my problem, any advice on what I can do to help with that? I read somewhere that adding an airstone could help but then I've also read that they don't do much in saltwater tanks.

Fortunately I do have some ammonia detox and PH stabilizer as well as some bottled bacteria handy. I will proceed with the water change right away and dose the ammonia detox and bacteria after that. Should I add the PH stabilizer too? It sounds like I won't need to, you guys seem much less worried about it than I was!! Thanks again for the help I really appreciate all of the quick replies.

pH is looking better. The previous mentioned was low but not to a critical stage.

My hopes are that your ammonia test is a false reading.

FishyFish · Feb 3, 2019

tupes said:
No dont add nothing else but the bottled bacteria. Adding too many things at once can really throw off your system

Invest in some good test kits.

You dont need them all at first but you at minimum have phosphate nitrate nitrite ammonia on hand.

Salifert is a good brand to start with.

Thanks for the advice, Tupes! I thought API would be great based on the Amazon reviews, disappointed again. I'll pick up a new kit ASAP.

You guys might be right about the false ammonia reading. I just tested it again along with some tap water and they're almost the same color only the tank water is cloudier. Tap water is on the left.

tupes · Feb 3, 2019

Looks like there is a green tint to the one on the right. Api is bad for low levels. If money is a problem I'm sure there is somebody close by that wouldn't mind you using their test kit to test your water

FishyFish · Feb 3, 2019

It's not really a problem, I'll be heading out to my LFS later today. Hopefully they sell Salifert...

tupes · Feb 3, 2019

Likely they do. Salifert RedSea and hanna instruments are the 3 most popular.

FishyFish · Feb 3, 2019

I had to go to four different fish stores but finally found one that had a Salifert kit in stock. It's still hard to tell but I think it's reading somewhere between 0 and .10. I'll have to check it tomorrow when there's better lighting to be sure but it's definitely nowhere close to .25.