# New filter, ph crashing repeatedly!!



## Catherine (Feb 22, 2006)

Hi all. I am flabbergasted. I have been running for 5 months with no problems, a 20 gal planted tank with and aquaclear and full of plants with the following fish: 15 cardinals, 7 rams, 2 chinese algae eaters and 1 cory. Two nights ago I changed the aquaclear filter out and put on a new fluval 204 with my old sponge tucked in it. The next morning, 12 cardinals were dead and two rams dead. Three of the cardinals were out of the tank on the floor. I thought maybe the ceramic rings in the fluval had dropped the ph.. IT was 3.0!!!! I did a 75% waterchange and the remaining fish (2 cardinals, three rams etc) seemed happy. This morning... ph down to 3.0 again and the last of the cardinals dead. :frusty: What is happening??

I run a DIY yeast CO2 generator, with a new glass coil diffuser instead of the ladder one that came with the kit. There is a bit of CO2 coming out of the glass diffuser (one small stream of tiny bubbles, but not the massive bubbling I have seen from ppl with Co2 canisters)

Why is my ph crashing like this at night and killing my fish all of a sudden? Is it the fluval? I did another 50% waterchange after fishing out the dead ones this morning.... 
Catherine


----------



## hoppycalif (Apr 7, 2005)

The only way the Fluval could affect the pH is by adding good circulation which mixes in the CO2 much more efficiently. Only the CO2 would drop the pH that much. Another possible problem is a drop in KH, which would drop the pH at the same ppm of CO2. A peat cartridge in the Fluval could possibly do that, but they don't come with one.


----------



## CherylR (Aug 12, 2004)

You are getting more CO2 into the water now because the Aquaclear causes more surface turbulance than the canister filter. Before, some of your CO2 was diffused into the atmosphere. Now most of it is circulating in the water, and the plants aren't using it up fast enough. 

I don't know if you can "turn down" the CO2, so you either have to make the plants grow faster by figuring out what ferts/lights to add, or go back to disturbing the water surface. That would be simpler. I run a powerhead aimed at the surface at night, but an airstone also works.

I'm sorry about your fish. This has happened to me, too.

Cheryl


----------



## Bill Weber (Jul 17, 2005)

I run an airstone at night and noticed a .5 increase in ph by morning.


----------



## sangpeiris (Jan 14, 2006)

Sorry to hear about your fish. I got ambitious and bought too many Albino Cory's. You can have one or two if you like. But, you will have to pick it up from my place. Drop me a note at [email protected] if you like to have one.


----------

