ph Question

[packagerat]

My tank is 8 weeks old now and the ph fluctuates between a low of 7.6 to 8.1. A week ago I started to add Seachem Marine Buffer to help stabilize it. If I add daily it will stay around 8.1. Is this just part of a new tank setup

 

[roka64]

It will depend on what time of day you test. Night, after lights out is lower than after lights on. Try to test at the same time every day. That sounds like a rather large swing, through the day. What kind of lid do you have?

 

[packagerat]

I keep the top completely open with my return line aimed toward the surface on one side and on the other side a Maxijet 1200 aimed at the return. I have quite a surface ripple.

 

[roka64]

Are you testing at night, during the day, at the same time each day?

 

[packagerat]

I have a Pinpoint ph monitor that I check frequently. In the morning it is around 7.8 and the evening usually 8.02. Since using the buffer it is 8.0 in morning and 8.17 in the evening.

 

[roka64]

I believe you will always have to add that chemical. What salt are you using?

 

[packagerat]

Iam using Instant Ocean Reef Crystals

 

[roka64]

I just switched to that from IO, so I don't have a comparison, since I haven't mixed any of the RC yet. In other words, I am at a loss, other than better surface ripple (gas exchange), but it seems you have that covered. I used to have a lid, even with the "punch out" plastic punched out, I couldn't get a higher pH.
Do you actually have a lid or are your lights suspended over the tank. I know you answered with, "I keep the top completely open", but I'm not sure if that means no top or a cover with the "punch outs".

 

[packagerat]

Sorry, no lid at all. My light is about 8 inches above tank.

 

[Hara]

another thing you might want to do is recalibrate your ph meter...

 

[melosu58]

Just another idea,PWC`s will also buffer your water. How often are you doing them?

 

[packagerat]

I have been doing 3 pwc a week. 3 Gal. each time. the lfs said I should hold off for a couple weeks. Any opinions on this?
Amm-0
Nitrite-0
Nitrate-0
SG-1.025
Phosphates-0
KH-14

 

[tecwzrd]

A lower ph reading the first couple of months is fairly normal for new tanks IME. Mine have always read around 7.8-8.0 the first couple of months but stabilized closer to 8.2 after that. Adding too much buffer will have a negative effect and could cause it to crash.

As long as it's 7.8 or higher I'd stop adding buffer and try larger pwc.

As Hara said I'd recheck the monitor and also check it with a chemical test like AP or check with your lfs to make sure the level is correct. If checking ph with the lfs make sure it's checked within an hour after removing from tank, it drops naturally over time kept in an air tight container.

Why are you doing 3 gal changes 3 times a week on a 72 gal? Why not do 10-15 gal pwc once a week? That's 15%-20% and won't hurt your stock. Currently you're changing out 5% every other day which is more time consuming and not as helpful.

 

[packagerat]

I have checked it with the AP ph test kit, same result. I have read were small water changes multiple times per week were a better option. Also I can do a 3 gal pwc without shutting off my pump. But I will try larger ones once a week to see if that helps.

 

[tecwzrd]

Small water changes are better versus large 40+% changes because it changes the waters chemistry very little. You are doing 15% pwc weekly now but at 5% 3 times a week. IMO that's more work then it's worth.

Larger 15% pwc weekly won't harm stock as long as you closely match the ph/sg/temp to the main. Plus you only have to do it once a week

Personally I use a 30 gal clean trashcan to store/mix my pwc water. I run a Mag 9.5 pump in it to mix the salt and the pump also heats the water to 79 degrees constantly so I don't need a heater. When it's time to do my weekly pwc I drain 10-12 gal to the toilet and then hook up a hose to the pump to pump the new water into the tank. The whole process takes less then 10 minutes and is mess free.

One other note is I wouldn't add the buffer to the tank directly and either mix small amounts (1/4 teaspoon) to your fresh top off water or a little more to your pwc mix. How many teaspoons have you added so far in total?

7.8 ph (especially in the morning) isn't drastically low and more then likely is the result of the salt mix you are using. Over the next couple of weeks you should see it slightly higher. Even if it stays around the 7.8-8.0 level any fish/inverts you add to the tank will adjust once you drip acclimate them.

If your tank is already cycled I'd add small amounts of food (nh3 source) to keep your bacteria from dieing off before you add fish/inverts.

 

[rubikcube]

Looks like the marine buffer is raising your KH too much. I'd recommend cutting back on that and checking your calcium to see if it has been adversely affected. I'd also stick with the 15 percent weekly water change. Also, what is your GH?

 

[melosu58]

I agree with 10-15 % PWC once a week.

 

[packagerat]

Total buffer added over 8 days , 9 tsp. It was added in slowly thru pwc and my makeup water. My Calcium using the AP test kit is 16 drops which is off there chart. My KH is 16 drops and my GH is only 1. I use RO/DI water for all my water. The water does go thru the house water softener before the RO/DI. I started on Monday to adding just plain makeup water. Will start doing the 15% pwc once a week which will be nice.

 

[rubikcube]

Something has to be wrong here. GH should be higher than KH since KH is just a component of GH. Having to use 16 drops in the KH test sounds extreme though.

I've never used the AP calcium test, but I would assume that each drop is equal to 20 mg/L. If this is the case, then your calcium is actually at 320 mg/L. This is pretty low as you should shoot for around 400 mg/L.

I would strongly recommend looking into why that GH number is off. Also, Instead of doing a 15 percent change, I'd recommend maybe a 20-25 percent change at first to balance this out a little faster.

 

[Kurt_Nelson]

My Calcium using the AP test kit is 16 drops which is off there chart.

Yup... something is wrong. I use the AP test for calcium also, and 16 drops equates to 320ppm - and is listed on the chart on their instruction sheet. The chart on my instruction sheet actually goes up to 26 drops (520ppm). Not sure why yours doesn't. Whatever the case, if you're using AP for calcium, then just multiply the number of drops by 20 and that's your reading.