help with ph gh and kh?

Question

i set my tank up about 2 months ago and i am keeping one angel ish in a 30 gallon tank with 2 catfish and somge ghost srimp i know i should just let the ph be but it is 8.4 and my gh was 300 ppm and my kh was 300ppm i have started using ro water to try to lower things every water change i am doing 2 a week so the water wont just get hard again but the ph is still 8.4 i recently added a rena water softner pillow to my canister filter and over night my gh went down to 0 so i got scared that such a change would hurt my fish also the kh went downto 120ppm which according to the strips is ideal the ph is the same i know the pillow doesnt affect that but if everything else is soft and the kh is ideal will the ph matter and will the water stay that way or do i have to recharge the pillow every 48 hours like it said to which means i have to turn my filter off every two days to do it yeah sorry if my question is all over the place pleace help

Answer 1

I'm with Jon and GHapy here, the RO water will take care of the problem without the softener pillow. Ditch the pillow in favor of more reliable and safer methods. What I see is that your entire hardness (or almost) is made up of kH. The pillow you have used removes the calcium and replaces it with sodium so that the hardness no longer reads on a test kit. More importantly, that change prevents the kH from buffering against pH changes.

A 0 kH is a cause for concern. I would well imagine that by the time you are reading this your pH has begun to drop. With a kH of 0 it will crash very quickly. and possibly fast enough to harm the fish, so I would suggest a 10% water change with tap water to give the tank a little buffer back before that can happen.

If you will mix RO water with tap at about 50/50 you should end up with a kH and gH your angels can live with. It will take a few weeks of regular water changes to effect the change, but that's a good thing, you don't want it to change too fast. Exactly where that will leave your pH could probably be calculated within a very reasonable guess, but it's enough to know that it will be much lower and will be stable at a comfortable range for your fish.

Since you will need to do this for the life of the fish and the tank, you might consider investing in a RO unit that will provide you with the 4 gallons or so of RO water you will need each week. A small inexpensive unit will provide that much with ease.

And please, whatever you do, don't try to use pH adjustment chemicals from the pet shop! WIth the other changes taking place in your tank water it could easily spell disaster!

If you need more info on water chemistry feel free to drop me an email.

MM

Answer 2

pH, gh, and kh can be very difficult to control. I used to have an East-African cichlid tank which needs high pH, gh and kh. My water came from a well with high gh and kh, but the calcium was dolomitic meaning the pH always returns to 7.

Your angelfish wants an acid tank with rainwater clear gh. Don't worry about your gh falling to 0; pH swings are more detrimental. My best guess is something in your tank is still causing the pH to remain high. Did you use gravel sold for aquarium use, or something local. Aquarium gravel supposedly won't affect pH, and often has a coating to prevent reaction with the water. You may need to use a pH Down product to lower the pH. DON'T TRY TO CHANGE THE pH ALL AT ONCE. Use only enough to change it half a point (8.0 to 7.5) per every two days at most till it is around 6.0, and test the pH daily. There are other products that should stabilize pH at this level which you can use with every water change. Below is a site where more info, and perhaps expert help will provide you with a better answer.

Answer 3

You are making the hobby more difficult for yourself and unless you truly think you can keep all this special care up for the long term, you may as well just leave your water as it was. Stable water is much more important then any one figure.

The R/O water should be enough to control things, if you must, mixed appropriately with tap water. The water pillow seems like a lot of work and money to get things down. You may just have not given it enough time.
First you should experiment without the fish and figure out what ratio of tap/R.O. water achieves the results you want. Mix them in a bucket by starting off with, say, 75% tap and 25% RO - and aerate it for a couple of hours before testing or the tests may not be accurate. Once you know what mix ratio you need, use this mix during your weekly water change. You should see the PH drop more each week.

If you use punctuation people will find it easier to read I usually ignore posts that just ramble on and on without any break or grammar cause it's really annoying do you know what I mean is this sentence as easy to read then the above I don't know you tell me.

Cheers :)

Answer 4

I don't get to see too many ph kh gh questions come up, and I'd lean on MM for support on this one, but my shot at this one, if the population you mentioned have been in this enviroment for the 2 months mentioned, I'd say your better off letting them stay in it. Most of the time, fish owners cause more stress adjusting the ph post occupancy of the tank vs adjusting prior to populating. If your fish were having problems with the ph I am sure you would have seen signs of abnormal behavior at this point. I'm about 6 years out of schooling practice here on kh though, truthfully. I think having a higher kh is actually better in most situations as other factors that enter the biosphere of a tank come in from time to time, that acts as a buffer to any rapid change. I'm going to lean on MM here to verify and consult because I'm not 100% confident I'm on the right track, but overall, don't mess with your ph too much, they are better off with a constant ph then trying to keep it at a 7.0.