Ph swings?!

[gex18]

My tank suffers from severe ph swings. For example on last water change ph was 6.45 (saturday), but today the ph controller is reading 5.12! It has in the past dropped as low as 4.72?! I have a juwel rio 400 tank filtered by an eheim 2329, s217, a fluidized bed filter, a uv sterilizor and a recentley added co2 kit from JBL (which has a solenoid valve and ph controller). Stock is 6 discus, 6 zebra plecs, 3 apisto nijjseni, 1 whiptail. Water changes are 15% twice weekly with 1.5 tsp of electro right added per 5 gallons, 5 ml of Sera kh plus per 5 gallons and 5 ml of JBL florapol per water change, but this hasno effect. The fish seem happy (discus spawning all the time), but these ph swings cannot be good for the fish. What can i do? I have shut off the CO2 but has had no effect. I thought that adding the sera kh plus would stabilize the kh and thus slowly raise the ph of the water? Also would switching from API electro right RO additive to a better make (like kent) help?

[Aurora]

I tried Sera kH plus. It raised my pH from about 6 to about 9. I tried it again just in a bucket of water, and it did it again. So I dont use it anymore.

You can buy kH powders that are better. I had one that was called kH 7.0, which raised the kH and set the pH at 7. You can buy other buffers that set and buffer the pH at either 6.5, 7.0 or 7.5.

[Dave76]

I was using a Tunze product called 'hardness granules' in my filter, it's actually a marine product for calcium reactors, to increase my gh & kh from 0 and to stabilize my ph so I could keep using my CO2.

I've recenting started adding some bicarb soda during each water change and found this works MUCH better - I add 3 teaspoons with each water change (about 300 litres) and this keeps my kh around 3 or 4, and I then set my co2 controller to keep the ph at 6.8 - which gives me co2 of between 15 & 20 going by the charts around (and confirmed with a co2 test kit aswell)

If you are going to start dosing new stuff I recommend trying first in a different container of water first before trying anything in your tank.

Regards

Dave

[gex18]

Ok, before i performed a water change, the GH was less than 3 d and the KH was 0. Didnt have chance to test after water change. The ph meter was showing 4.94 before change and 5.30 after.

[Merrilyn]

Gex, that's quite a mix of chems you're adding to your tank. I gather you are using RO water. I'd be interested to know the pH of your water as it comes out of the tap. Where are you from.

[gex18]

I have stopped using the florapol, i am using just electro right and ph adjuster now. Have been advised to use bicarbonate to get the kh to around 4, how much sould i use (tank is 400 lire)? Will it cause a maasive increase in ph (as my meter reads down to 0.01 ph changes?)?

[Majesticaquatic]

About 2 years ago Kent Marine came up with a product called "Low Range Controller" Ph 6.0 percise...
I have been using it since it came on the market and must say that in 44 years I have NEVER used such an awesome product...
Not only does it do a superb job of Ph controll BUT it also softens the water gradually to 0ppm (from the tap my water is 8.2/8.4 and hardness is 400/600ppm, both dependent on time of year.)..
Product works on Ph INSTANTLY and has built in buffers so it can be used EVEN if there are already fish in the system..... With-in 2 weeks Dh is down to 40/60ppm, usually with-in a month Dh is 0ppm [how often water changed will have an affect on these results]...
If you are having trouble controlling Ph give this product a try, believe you will be very pleasantly surprised at it's effectiveness and ease of use. :wink: