Super High pH - help please

[pinkpetal256]

I have had my tank for about 3 months, and have had many deaths of mollies, gouramis, guppy and tetras.

I have measured all the water stats every few days for the last few weeks - and they are all fine (Ammonia 0.1, Nitrate 5, Nitrite 0) but the pH is sometimes off the scale! Sometimes it's around 8.4 (it's 7.4 out of the tap), but a couple of times it looks like it is over 9!

What can i do??? Help!

 

[black angel]

what have you furnished the tank with.

 

[pinkpetal256]

Washed aquarium gravel, planets, 2 rocks (i'm not sure what these are, but one is very pearlescent and flaky - both bought from a fish shop that new we were starting up), and bogwood (soaked for a number of days).

 

[Shizat]

If you let your nitrates build up to around 30-50 they will probably bring your ph down few decimal points and then do water changes weekly.

 

[luxum]

I suspect the rocks are leaching and driving up the pH, try removing those (one at a time, let the water stabilize before you remove the second one) and i suspect your pH will drop back to normal as you do your regular water changes. Remember to let the change happen slowly so as not to stress the fish with a sudden shift in pH.

 

[littleme1969]

Bogwood/mopani wood is good for lowering PH slowly.
Also add a Co2 source will also bring down the PH. You buy eas to use kits now for about £15.00.. You just rinse out and add new sugar yeast etc every month..easy to do and easy to maintain.
Livbearers are particulaly sensative to high PH I had the same problem myself for a while. Maybe ask the shop where you get the fish from what the PH is in their tanks.. and test some when you buy fish next time to be sure. The general rule is if its more than 0.3 up or down difference from the tank that you are putting the fish in..then try to find a shop with a PH more like your own. Otherwise PH shock will have a big affect on thier health when added to your tank.

Also always leave your tapwater overnight before you test to get a more acurate reading. Water coming straight from the tap is full of carbondioxide which will dramaticaly lower the PH.. once this as evaporated into the air the PH always rises.
Mine is 7.4 straight from the tap and 8.0 when left overnight. But with bogwood and CO2 the tanks run at about 7.7/7.8 so it does really help to pull the PH down to a more fish friendly level.

Hope your get on top of your problems