MY wife and I have had aquaria for years, both fresh and salt. We would love to try some discus fish. Here is our dilemma. Our city tap water has the following characteristics. PH-8.2, GH-110ppm KH-90ppm. Now my sister is on a well and has the following, PH-8.2, GH-50ppm and KH is off the scale over 500ppm. Obviously either water we use, the Ph is going to have to be dropped drastically. MY question is, wouldn't we be better off using her water due to the lower Gh and higher Kh. Doesn't the higher Kh act as a buffer against Ph fluctuations? We also tried a 50/50 mix and didn't change much except for bringing the Gh up to about 75ppm.
Starting some discus fish.
- Thread starter llsimpson
- Start date
The amount of KH necessary to prevent pH swings is not that high...the 90 ppm in your tapwater should be more than sufficient. In fact, given that discus prefer water with a pH around 6.5 and very little GH or KH, you might want to consider buying a reverse osmosis water filter and mixing it 50/50 or so with your tapwater to bring the ph and hardness down still further. A small system is available from any of the on-line retailers for less than $100; I highly recommend that before you spend all that money on the fish you make this investment in the equipment.
BTW, since discus require massive water changes and filter cleanings to remain healthy in any case, even with lower KH you shouldn't have any problems with pH swings.
BTW, since discus require massive water changes and filter cleanings to remain healthy in any case, even with lower KH you shouldn't have any problems with pH swings.
I agree with what Harry said. A RO unit would be your best bet. Discus like a KH and GH of 2 to 4 degrees. Water with a higher KH and GH would be resistant to pH lowering due to buffering properties of the harder water. So if you are planning on lowering pH with chemicals, using your sister's water, you will be fighting a loosing battle since your sister's water has a huge buffering capacity. Your water isn't that hard, KH is about 5 dKH, GH about 6 dGH. pH a little high so a mix of RO/tap 50/50 would work nice, even 40/60 would be good.
I agree with Deb2, who agreed with me. Just one final point for reference purposes. 17.9ppm = 1 dGH or dKH.