pH Control for Fish Health

[r0bin]

I use walmart distilled water and I always make my water at 1.025 which is where I keep my salinity at in my tank. The PH has been 7.8 in my tank for over a year and the current fish I have must be able to handle it thats why I have left it alone, but I think the angel is more sensitive. Is there an additive I should be using on the distilled water for it to have a more proper ph after its mixed? You are very helpful and I appreciate that. Thank you very much.

ps. I appreciate you helping me b/c I have left post about this problem at more that one website and no one really every seems to have a solution. I just tested the 2 gallons of saltwater I made yesterday using wal-mart distilled and it is 7.8. Also another note, I one time did buffer my ph up to 8.4 using Seachem liquid marine buffer, but it dropped back down to 7.8 within days, so I dont know if the distilled water just can't hold it where it shoud be or what. Thanks again, I REALLY what to get to the bottom of this problem, it has been a thorn in my side form day 1.

[leebca]

I've moved these last posts to a new thread to keep the subject separate, if you don't mind.

If your aquarium water can't hold a pH then the matter is usually that the buffer can't cope.

This means (to me) that either the buffer is too weak or the onslaught of acid is more than a normal buffer can handle.

But before you launch into making changes, are you sure your pH is that low? Are you sure you are testing it properly? What are you using to read/measure the pH? Have you had the pH verified by someone else using another testing method?

Distilled water is 'clean' but it can be very acidic and still be clean. Check the pH of the distilled water you're using. Check (if you can) several different containers of it to see if it varies.

Part of the reason I suggested you post to get pH control recommendations is because I am a chemist/microbiologist by trade. I use chemicals the general public doesn't have access to, to control my water chemistries. I'm not that familiar with the shelf products for this sort of thing, so I can't recommend them.

I am unfamiliar with Instant Ocean. Some people have said it does not have a particularly good pH buffer. I don't know. I use Tropic Marin (not that I'm suggesting you change).

There are a number of things that can lower pH. The carbon dioxide source is the most common, and carbon dioxide can come from several different sources. Carbon dioxide can come from some very surprising sources. One source is if you have decaying matter in your aquarium (where you can or even can't see it) that is a potential source of creating too much carbon dioxide in the water.

Anything(s) dying? Any detritus in your system? Have you been keeping things clean? Is your LR (if you have any) dying off or causing a problem? Are you also checking regularly for ammonia and nitrites? What readings do you get from those tests?

In short, you have to play detective to find places in your aquarium where bacteria are taking over, or going crazy, where there is decaying matter, or an unusual or high carbon dioxide source.

Dr. Randy Holmes-Farley is much better at the pH issue than I am. I suggest you read this one article for sure:
http://www.reefkeeping.com/issues/2004-09/rhf/index.php

I know the above is full of technical information. Just scan that part and go down to about 2/3 through the article for more practical help.

If you've addressed the bacteria, decay and excess carbon dioxide in the room possibles, then next attack improving the alkalinity. You'll have to gather alkalinity measurements using a reliable and good test kit that is current (not outdated) and that provides detailed analysis.

Since pH is connected to alkalinity, and alkalinity is connected to calcium, I suggest you start performing regular alkalinity and calcium measurements. Use Salifert test kits since I find they give good details. You will need to check not only your aquarium water, but the makeup water for these things. Let's get 'before and after' numbers.

Water chemistry control requires frequent measurements and involvement at the outset, then when the tank matures and settles, you can sit back and enjoy it more often. Until then, daily tests and adjustment every couple of days may be needed until you bring this matter under control. In the long run, the pH control should not require a lot of attention.

That's all I can think of to start with. Sorry you haven't been getting the help you need/want. I'll do my best.

[r0bin]

Again thank you for your help. To answer a few of your questions, I regularly change water and vacuum my substrate. My tank is pretty clean. I think the problem lies with the water I am using. When I make my salt water the ph is never higher that 7.8. This means to me that when I put it into the tank is isn't going to just jump up to 8.3. I am almost sure this either is the water I use, or possibly the carbon monoxide problem I have read about, but if I had to guess, I think its the water. I am thinking I need to add something back to the water that is apparently missing through the distillation process? Also my alkalinity is alway pretty high. I use the five in one test strips on my tank for there convenience. I know people say they are not very accurate but when I had the another test kit, the kind your mix your water with I got all the same readings as I do with the strips. Also I tested my LFS water with the strips and their PH immediatly went in the correct range on the strip. Therefore I beleive the strips are pretty accurate and my ph is low.

[r0bin]

I just tested the distilled water I used straight out of the jug. The PH of it test around 6.5. The alkalinity is zero! Ok where do I go from here?

[leebca]

The pH of distilled water is tricky to take, since there isn't much of anything in it. But, I'll take your test strip reading for now.

I'm afraid if you are going to do the careful work you need to do to move the pH to between an 8.3 and 8.4 you're going to have to give up your test strips for the accurate work we have to do.

Strips can't test for Calcium and we need to know those numbers to three significant figures. Time to scale up to titration test kits and a pH meter.

I use the strips myself for a rough check now and then. But they are not going to do the job for deciding how much chemicals to add and the effect the chemical addition has on the water, and lastly they can't tell you the Calcium content in the water.

I'm talking needing three significant figures on Alkalinity and Calcium measurements. I'm talking at least 3 significant figures on your pH (e.g., I would need to know if your pH went from 8.21 to 8.27). It's these kinds of accuracy that leads to good control and good stability. If the only thing you can tell is if the pH is 8.3 or 8.4 that isn't good enough for making adjustments.

You don't have to abandon your test strips, but they will only be used later for general information, not for the needed accuracy for adding chemicals.

The Alkalinity of distilled water would be expected to be zero, so that's okay.

Time to shop (at your LFS or on-line):
Buy the following test kits (I recommend using Salifert Test Kits):
Alkalinity
Calcium

Buy a pH meter:
I'd recommend a hand-held pH "field" pH test meter and standard solutions of 7.0x and 10.0x to calibrate it with. Although Hanna might make one of the best, you can find others that will do.
---
Then with the pH meter in hand:
Add baking soda to the distilled water in quarter teaspoon quantities, making sure each quarter teaspoon dissolves, checking the pH, then if too low add the next quarter teaspoon.

Put baking soda in your distilled water until you get a reading of 8.4 pH, then make up your saltwater like you normally do for a water change. Record 3 pH numbers: distilled water pH before you started; adjusted pH on the distilled water; and the pH of the newly prepared saltwater.

After you have those test kits & meter:
I want you to do an Alkalinity test on:
1) your tank water AND
2) the freshly made saltwater with the higher pH
I want you to do a Calcium test on:
1) your tank water AND
2) the freshly made saltwater with the higher pH


Tell me the quantity of water you're using for the above. Tell me how much baking soda you used. (Using a quarter teaspoon measuring spoon).

After you have all that data (from test kits and pH meter), we'll go from there.

Give it some time and money IF you want to go beyond the common hearty fishes.

[r0bin]

I have been dosing my 75 gal with baking soda. 1 teaspoon in the morning and 1 teaspoon at night for the past 6 days but I have not seen any noticeAble chage in my ph. Am I not dosing enough?

[leebca]

Sodium bicarbonate additions are mostly for small, little changes. The truer chemistry is that pH is related to alkalinity is related to calcium concentration. If the other concentrations were known accurately, the way to adjust would be more clear.