Ph = 6.4

[tennis4you]

My tap water is pH 6.4 after it sits for 24 hours and it is of course 6.4 in my tanks. I would like to make sure I keep fish that are OK in 6.4 pH water. Can anyone recommend any? I have a 125g fresh water tank.

Thanks!

 

[Tommy Gun]

Hey tennis4you!

While I will not be surprised if a number of hobbyists disagree with me, IMHO and IME, pH may be slightly less of a concern for you right now - or at least when applied to a FW tank. My reasoning for saying this is simply that freshwater fish have a relatively strong ability to adjust/acclimate to a wide range of pH if given enough time to do so. In fact, many people would say that your best bet would be to ensure that the pH in your tank remains as constant as possible or does not change frequently or rapidly since this would place additional stress on your fish. That being said, I can all but guarantee you that, if the pH remains constant and stable, a freshwater fish will not die simply because it is not being kept in a tank which does not mimic the water chemistry of its natural habitat. One very strong argument to support this notion is the simple fact that a very vast majority of hobbyists can and do keep various combinations of community fish which otherwise would never be found swimming together in nature without any overly adverse issues due to pH. I can also tell you that I am currently keeping a few African cichlids in a tank with about 6.8 pH (versus the much higher pH of their natural habitat) and have been breeding them for a long time - although, this doesn't mean it will work for every type of fish. Additionally, in many cases we are bringing home fish which are 'tank raised' and hence, may have never lived in any sort of natural waters.

You may also benefit from the low pH of your water because, when under 7.0, much of the ammonia is 'transformed', for lack of a better term, into less toxic ammonium...which, in reality, shouldn't be an issue in a cycled tank anyways, but it does provide some 'wiggle room' for making mistakes and such. Don't worry though, beneficial bacteria can still 'use' ammonium as a food source, so the loss of an ammonia source will not result in your tank becoming un-cycled. In fact, while some products may actually remove ammonia, those dechlor conditioners such as Amquel+ and Prime (I believe...never used the stuff) which claim to detoxify ammonia do so by creating ammonium.

Conversely, there are quite a few fish which will do well in lower pH, and of course, you could attempt to buffer your 6.4 pH to something higher, but my suggestion would be to use a more permanent method of doing so since, like I said, the use of temporary pH buffers could result in large or rapid pH change if you are not completely vigilant.

 

[raptorrex]

hey Tommy Gun, an interesting, well written and logical post.
my only concern is that over a long period, at much lower than normal ph, the fish may require some addition to help make up any shortfall. however i emphasis this is just a feeling. perhaps those with more knowledge, could enlighten us more.

 

[ShoC]

Great Write up Tommy gun

 

[raptorrex]

tennis4you, you dont say what fish you are keeping. some fish are more sensitive than others. you can use crushed, not powdered coral. this is put, or should i say often put, in a mesh bag and placed in the tank. some say to put it under the inlet of your filter and some advise placing it under your gravel, both methods are said to work.

a good rule to use is, how was the fish kept, at the LFS, prior to you purchasing it. if it was kept in tap/dechlorinated water, and you trust the shop. there seems little point in making any adjustments. if it was kept in modified RO water, PURE RO has a lower ph than your tap water, then it may be advisable to try to adjust your tap ph. be warned though, trying to make and maintain, adjustments to your tank water, is far from simple. remember wild swings in ph are very possibly more dangerous to your fish, than keeping them at a lower than advised ph. worth noting though is that to raise your water from 6.4 to 7.4 would require a ten fold increase in alkalinity

sadly, it may be that it is just better not to keep that or those fish

 

[ibbledibble]

My tap water is pH 6.4 after it sits for 24 hours and it is of course 6.4 in my tanks. I would like to make sure I keep fish that are OK in 6.4 pH water. Can anyone recommend any? I have a 125g fresh water tank.

Thanks!

i may be wrong, but the way i read this post, it sounds like tennis4you does not have fish in his tank yet and is asking for stocking advice for future purchases. is this right?

in which case the point raised by tommy gun is totally valid.

but
angel fish generally like ph of below 7
blue rams generally like ph of approx 6.5-7 so not far off there
discus generally like ph 5.5-6.5
the majority of bettas like neutral (ph 7) to mildly acidic water so should be fine
most tetras like ph of between 6-7 although in the wild the neon tetras can be used to more acidic water going down to 5.5
tiger barbs generally like a ph of about 6.5
danios and rasboras all tend to prefer neutral to slightly acidic water
catfish are best kept in neutral to acidic water
oscars like a ph of about 6.5-7

generally you would want to avoid things like livebearers as they prefer more alkaline water, but again they will tolerate it as long as the ph remains stable
fish such as mbuna cichlids are also used to hard alkaline water

i am not suggesting that you keep all of the fish mentioned together, and its not a comprehensive list, thats just a few suggestions to get you thinking.