high ph?

[Yellowfin]

I have recently switched from salt water to fresh water. I can't seem to get the ph to the proper levels. Even with ph down chemicals the ph climbs right back up to 8.4-8.6. I have done many water changes adding ph down chemicals only to have it clims back up immeditaley. Could it be that the gravel bed is made from crushed coral even though it is more that ten years old? Please help. Thanks.

 

[hollywoodH]

What fish do you have in there??

 

[Yellowfin]

It's a 55 gallon tank with:
2 cat sharks
2 anglefish
3 tiger barbs
2 tin foils.

any thoughts would be appreciated

 

[PunkRock050]

My problem is exactly the opposite, I cant keep my Ph that high for my Cichlids.

Try putting some driftwood in the tank. They have lots of nice peices on Ebay. Thats where I got both of mine.