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Changing From Bottled Spring Water With High Nitrate to Tap Water With High pH

3171 Views 16 Replies 4 Participants Last post by  Mikaila31
I am new to fishkeeping and over the past several months I have successfully cycled 4 tanks that I have been filling with bottled spring water. The water parameters in my cycled tanks are: pH-7.4 Ammonia-0 Nitrite-0 Nitrate-40. The Nitrate level of the spring water straight out of the bottle is @30ppm.

I would like to switch my water source to plain tap water with the following paramaters: pH-8.8 Ammonia-0 Nitrite-0 Nitrate-0.

Is it possible to safely change the water over to tap water with such a high pH level or do I need to use something to adjust & regulate the pH before each PWC? Would it be better to use half bottled/half tap? Through research I have read that fish can adjust to different pH levels but I'm afraid that the 8.8 will be too high? Thanks for the help!:-?
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What size tanks do you have? Solution will probably be different if they are 55 gallons vs 5 gallons :)
That's true jaysee! I have a 37, 26, 20 & 10. For convenience sake I would like to get away from bottled water altogether- if possible.
If I were you I would keep African cichlids :)

But really, if you want more neutral water then you'll have to play chemist. You might want to look into a holding tank from which you can pump water to the tanks, that way you can get the water where you want it and move it. Probably easier to do with a larger volume of water, too.

Your other option would be to get an RO machine. An investment, but you can be sure the water you get is pure and neutral. Will also be good for drinking water so it's dual purpose :)
I did purchase a couple of 5 gallon buckets and mix up a batch of lower pH water using Seachem Neutral Regulator. It required double the recommended dose to get to 7.4-7.8. I spoke with a company rep who said that shouldn't adversely affect my fish. I also contacted the water company about the GH level which is 100ppm-soft. I think the lower GH reading helps stabalize the effects of the Neutralizer.

Does an RO machine lower pH? I wouldn't mind investing in one. In the long run it would save a lot of hassle and money. Plus, our water tastes terrible so it would benefit us earth dwellers too!
RO spits out 7.0 pH water that is free of everything. You'll have to switch to an RO water conditioner, which replaces nutrients as such that the RO process removes.
KH level tells you how stable ph changes will be in your tank. My guess would be that your KH is low and that changes made to ph via products made to raise or lower ph would not be very stable. More permanent adjustments can be made through the use of buffering materials such as substrate, peat, etc. Sorry, I'm not very familiar with the various methods...just know they're out there. The best choice is usually to stock according your source water chemistry. Of course, that can be very limiting at times.
Need to know KH and GH of current tap water. pH really does not tell you anything. Your tap water may be fine to use without changing anything but you need to know much more the pH. pH isn't as important to fish as most ppl seem to think.

RO is a hassle to use given how long they have to run and then the mixing or remineralizing. pH wise it may come out around neutral then RO goes acidic pretty quick if its left out. Straight RO is not suitable for drinking water.

Have you tested your tap after letting it sit out for 1-2 days?
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Thanks for the input and advice everyone!

Mikaila31- I will do as you suggest and test my water on Monday. What other tests besides KH, GH, pH, Nitrite, Ammonia, & Nitrate do I need?
I was under the impression that bottled water was RO water.
Bottled water varies, a lot of it is spring water and like the OP found out can actually have significant nitrates and such. The rest is usually filtered tap water that is then bottled. It is rarely RO water. RO generally isn't sold as drinking water since it is completely stripped of minerals, elements, and natural electrolytes. Water does not like to be pure. Life does not survive in pure water, thats why we remineralize or mix RO water with tap water. Some people do drink RO water for better or worse, but it has the tendency of pulling minerals out of your body, especially calcium. I'm sure they sell products to add to RO water to make it 'super healthy' drinking water. RO water in general tastes like crap IMO, water is tasteless and you store it in plastic so then it tastes like plastic. Typically the more 'stuff' in water the better it tastes. My current tap water isn't the best but it tastes okay. My folks well water with almost double TDS and 25ppm nitrates is great water and my plants loved it too.

Lilybelle - look online for a local water report as usually this is public information. Either link the site here or copy and paste whatever info they offer.

Your low GH and high pH make me wonder if your water suppliers are using corrosion prevention methods, since naturally soft water will corrode water pipes long term its not uncommon for them to jack the pH up to prevent this. It would depend if KH is also medium to low. If it is then the abnormal pH isn't as concerning and not that important with the fish.
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Always a wealth of information, you are :)
Thank you Mikaila31! Here is the link for the annual water quality report from my water provider. The most recent data is from 2011:

Mustang Special Utility District

I appreciate all of the information and help that you are providing!
After sitting for 2 days my tap water parameters are: pH-8.8 Ammonia-0 Nitrite-0 Nitrate-0.

I also tested GH & KH with the API Test Kit but I'm not sure how to interpret the results.

KH- It took 20 drops before the test sample changed from blue to yellow.

GH- The test sample was never orange. The 1st drop of the reagent produced a light green color.
Wow, you water is basically liquid rock if GH is that high. It depends what you are keeping. The pH adjusters are a waste and really don't do anything. Its the high GH that makes the water very hard and gives the high pH. The pH adjuster is basically adding acid to bring the pH down artificially. It doesn't change much of anything from the fishes perspective the water is still very hard.

Doing an RO mix is an option, but with the really hard water you will likely have to replace filters and membranes more regularly then most which isn't terribly cheap.

If your fish are hardy tropicals they should be fine overall. As jaysee said before tho the african cichlids are best suited to this water.
Now I'm confused... I thought that, based on the test results, my water was very soft. I thought a lower GH indicated very soft water??
Oops I meant kH in that last post. Both GH and KH are different types of hardness. KH is carbonate hardness and is due to your tap water being sourced from ground water. Likely a lot of limestone down there.

If you live in a fairly rural area,(low smog) you could collect rainwater in a barrel and mix it with some tap water. The rain water will have no KH and will help you soften the water, that may not effect the pH very much tho.
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