Fluctuations in pH

[Jadedrain_06]

I have been trying to cycle two 10 gal tanks and my pH is all over the place. I don't have any rocks, coral, plants or wood that would contribute. Our tap is 7.0 and sometimes my tanks will go to 8.5. Is that normal? I know fish can adapt to different pH for the most part and I am just going to have community fish in one and a betta in the other. Should I be concerned?

 

[toddnbecka]

Sounds like the pH is rising after the CO2 outgasses. Test your KH and GH to find out how stable the pH will be in the longer haul.

 

[Jadedrain_06]

My KH and GH are always maxed is that a good thing for my longterm pH? I really don't want to add a bunch of unnecessary chemicals. I was trying to drop it the one day and added pH down and it went from 8.0 to 7.4. The next day it was back up to 8.0. Is that normal? I am a complete newbie and want to understand everything I can before I even think about adding fish. Thanks for your help.

 

[toddnbecka]

What do you mean the KH and GH are maxed? Biological activity produces organic acids. They react with the minerals in the water that maintain the pH. The higher the KH is, the longer it will take for the acid to break it down and start lowering the pH. When you add acid (pH Down) to the tank there's a short-term drop in the pH, but buffering capacity of the water will raise it again until/unless the KH reaches 0.
The GH is less critical, though some fish don't do well in hard water, while others thrive in it. Typically, livebearers like guppies, platy's, etc. prefer hard, alkaline water. Betta's originally came from soft, acidic water but have been tank bred for so many generations they're pretty well adaptable.

 

[Hholly]

I'm having the same issues. I got an airstone and some live plants to try to get rid of the CO2. At least as I understand it, that should help stabilize the pH.

 

[jlk]

Lets look at where your at in cycling. What are your water parameters (amm/nitrite/nitrate)? What are you using as an ammonia source? Have you done any water changes yet? PH swings can occur in the cycling process (mine always went up) and water changes will replenish the buffers to help stabilize the ph. How long have you been working on cycling your tanks?

 

[librarygirl]

Let a glass of tap water sit out for about 24 hours and test it a few times during the process and see if the PH rises/falls/or stays the same. This will let you know whether it's the tap water or something in the tank (or the cycling process itself) causing the fluctuations.

 

[Jadedrain_06]

I use the API test sticks and everytime I have tested with them the KH and GH are always the highest reading. I have been cycling one tank for about 4 weeks and the other about 2. The 4 week tank has 2 airstones and with the 2 week tank has 2 filters (one will be my hospital filter) and I lowered the water in the 2 wk tank so there is some splashing to help put O2 in the water. Does that work as well as airstones or should I grab one out of the 4 wk tank? I am using pure ammonia and right now each tank is at 4ppm. I am going to do a complete check of pH, KH, GH, Ammonia and Nitrites of both as soon as my wild one year old takes a nap. She isn't very patient lol. I did a water change 2 days ago of about 30% or so. Both tanks are not stocked but I would like to figure out what is going on prior to adding fish because I know major fluctuations can kill. Will do the tests ASAP!

 

[librarygirl]

Have you had any drops in ammonia in either tank? Is the cycle progressig at all? Do you have the API test kit for the ammonia, nitrite, nitrate or do you have strips for those as well?

 

[toddnbecka]

Get yourself a master test kit with bottles of liquid reagents, they're much more accurate/reliable than dip strips.

 

[Jadedrain_06]

I have both. I used the test strips to test KH and GH but the kit to test others. Still haven't had a chance since Little Miss is not being cooperative lol.

 

[Jadedrain_06]

Okay so I just tested both tanks.
2 weeks 10 gal: pH 7.4-7.6, Ammonia 2.0 (added 2.5mls to bring it up to 4.0), KH 80, GH 30, Nitrite .25, Nitrate 0-5.

4 week 10 gal: pH 7.8, Ammonia 4.0, Nitrite .25, Nitrate 0-5, GH 30, KH 240.

Is there a better way to check for KH and GH? I really don't think the strips are very accurate.

 

[librarygirl]

API sells a liquid GH/KH kit. Unless your GH/KH are very low or very high it probably doesn't matter much. As long as the PH stays stable it'll be fine for fish.

You have some nitrites in both tanks so that should signal the start of conversion unless you have nitrite in your tap water? Have you had any drops in ammonia at all in either tank?

 

[Jadedrain_06]

Today was the first day that I had any nitrites show up in either tank so I am assuming our tap would be negative. Got a little excited because I have been patiently waiting lol. The 4 week tank dropped from 4ppm last night to 2ppm today. From what I have read I just keep making the tank stay at 4ppm until I get nitrates. So I bumped it back up to 4. I have heard mixed things about water changes during a fishless cycle. I haven't touched them in a few days and wasn't sure if it was a good idea. The 4 wk one is looking super cloudy so I didn't know if I should.

 

[librarygirl]

No real need to do a water change during a fishless cycle unless PH drops dramatically or nitrites have been off-chart for a long time. It's a good sign that nitrites are showing up then. The cloudiness could be a bacterial bloom; perfectly normal. You can top off the water if it evaporates (just add dechlorinator first) and no need to add ammonia to the water if you are just topping it off. I don't see the need for a full water change yet though. Keep us posted!

 

[toddnbecka]

If you know anyone with an established tank all you need is a little dirty filter media to jumpstart your tanks.