Safe number of water changes

P

pkdiaz

AC Members
Feb 18, 2003
10
0
0
54
Visit site
I have had my 55 gallon aquarium for about a year now and my LFS advised me to add aquarium salt to my aquarium at each water change. I do a water change once a month. Because of the addition of the aquarium salt my PH has dropped really low to about 6.2. I have a community aquarium so this is not good. How often can I safely change the water to get the PH back up? I don't want to add any chemicals to raise it, because I know from experience, it won't work.

PS I was not aware that aquarium salt dropped PH until it was too late.
 
I don't know that aquarium salt would drop your pH. I do know that marine salts contain buffers to raise pH, but this would be a first for the aquarium salt. Do you have anything in the tank that would release tannins (ie, leaf litter, driftwood, peat)? These definitely will drop pH--the amount depends on how hard your water is.

However, depending on what community fish you have, you don't need to add the salt. www.skepticalaquariast.com has some great info, if you're interested.

As for water changes, you can do as many water changes as you need to, just do them slowly when raising pH. A 20% water change won't raise the pH that much, so if you do a 20% change daily until it's at a higher level, you should be fine.

However, and once more, it really depends on what fish you have, your pH isn't so low that I'd worry much. Heck, planted tanks would love that level. If you aren't seeing a problem with any of your fish, instead of concentrating on raising the pH, I would just quit adding the salt, and continue doing water changes on your regular schedule.
 
Aquarium salt does not drop pH. It may contain some alkaline buffers that may raise pH, but nothing that will cause it to lower.

Something else is causing the pH drop. What is your KH?
 
I had 2 other LFS stores tell me that the aquarium salt is what was causing the PH to drop. Maybe no one around here knows anything about aquariums. I definitely don't. The fish store that I buy my fish from told me to add aquarium salt and a water conditioner to the water at every water change. She also told me to add Quick Cure for Ick although I do not have any ick problems. I was told by others that the aquarium salt was causing the problem. Maybe it is a combination of everything. My aquarium before always had a high PH of about 8, but my fish were fine. Now my fish seem to be kind of sluggish to me but they don't look sick. I have 3 Zebra Danios, a loach, 2 algae eaters, 2 goldfish, and 1 tetra-thanks to my goldfish who ate the other tetras. I know the goldfish are out of place in my community tank, but they don't seem to mind, other than the fact one of them developed an appetite for neon tetras. Now my last tetra thinks it is a danio. As of this month, all I have done is add the water conditioner at the water change. I left out the aquarium salt and Quick Cure. I don't have any plants. I am new to this and right now I am doing good to manage fish. None of my fish have died as a result of my care except for the time I bought fish from Wal-mart. They all died within a week. Is there anything else I should do? I want to add more fish. I was thinking something small in a school to add color, but I don't want my goldfish to eat them. Maybe one day I'll add plants.
 
What fish stores are around you that you go to. If's its like petco, they don't know what they are talking about and just want to make a sale. That person who told you to add quick cure even though your tank is fine is a moron, don't listen to her. You are treating nothing since no fish are sick.

No, the salt will not lower the ph.
 
The pet store that gave me the ick advice was a small mom and pop store. The ones who told me that the aquarium salt was lowering the PH was PetSmart and another aquarium forum.
 
Definitely don't add any medications unless you have the symptoms. It stresses the fish, and can cause problems with the water quality.

In terms of adding fish...Well, let's find out a bit more. What size tank is this? One thing to note is that the goldfish, in addition to getting huge and making snacks out of tank mates, prefer cooler waters, while the danios and tetras like warmer waters. Long term, this might cause some problems.

There are people in all levels of the hobby that will give you goofy advice. I advise people to always think about the advice and research it. For example, you wouldn't believe it if you were told you needed to take cold medications even if you didn't have a cold, right? Same thing.
 
Agree with both the above, but will add a bit of my own feelings on the matter.

First ditch the salt additions. Salt (unless marine mix) will do nothing for you buffering, and in any case, the issues is elsewhere. Salt did not drop your pH, Old Tank Syndrome dropped your pH.

You have a year old tank with twelve total water changes of unspecified volumes. You have fish, which produce ammonia. Ammonia is oxidized to nitrite by bacteria. Nitrite is oxidized to nitrate by other bacteria. That nitrate stays unless you change your water sufficiently to remove it.

Step 1: Measure your nitrate in the tank. It should be below 40ppm nitrate at least. At best it should be at 10-20ppm. Do serial (daily) water partials until it is where it should be. Vacuum the gravel with every partial.

The nitrification process described of the bacteria oxidizing fish nitrogenous waste uses, burns up, the carbonate/bicarbonate buffering in the water. Each milliequavalent of nitrogen oxidized to nitrate from ammonia uses two milliequavalents of buffering - the units and measures are trivial to you, do not worry about them - just remember that when your tank's filters are working, the bacteria are using up your natural buffers while they are detoxifying the nitrogenous wastes.

Step 2: Measure the KH of your tap water and of your tank. They should be the same. If they are not, if the tank is lower, you have lost buffer and need to replace it. Regular, routine, preferably weekly, water changes will replenish the natural buffers in the tank with those in the tap water. Your GH in the tank is likely to be higher in the tank reflecting replaced evaporation over the last year.

Established tanks do not need a lot of testing when operating smoothly. They do need to be tested for nitrate at least monthly. If the nitrate is creeping upward, you need to increase the frequency and or volume of your water changes. If nitrate is stable and from 10-20ppm, you are doing just fine. If your tap water is low KH (KH 3 or KH <3), checking the KH at the same time is good also.
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom