Nitrates -30 & PH dropped to 7.8

[okiefish]

Ammonia and Nitrites are at 0 but my Nitrates jumped to 30 and my PH is showing to be at 7.8. This is the first time I've tested the PH and its been below 8. My Nitrates are usually around 10 or less. What could have caused the changes?
I have a 90 gallon w/
90lbs LR
Tomato Clown
Yellow Tang
Foxface
2 blue damsels
1 domino damsel
cleaner shrimp
coral shrimp
chocolate chip starfish
and snails and hermits

 

[rockies]

What kind of filtration and buffering do you have in your system? Have you done water changes lately?

 

[tizzo]

90 pounds of live rock is a good amount but not sufficient to be a main filtration source with 6 fish. So you can either add around 35 to 40 more pounds and/or reduce the amount of food they get (that's an assumption on my part, that I am going by since it's the #1 cause of nitrates).
If you have another source of filtration, please post it...

 

[ophiura]

As addition to my other post....definitely post if you have something like a canister filter or similar...and when you last cleaned it.

 

[okiefish]

I have a canister filter. I went ahead this evening and changed out the foam pads. I'm starting to recall that last time I changed out the filter I didn't have any foam pads. The "Fine" foam pads were pretty nasty when I changed it.
Could that be the reason for the Nitrate jump?

 

[ophiura]

Yes, and the pH drop. You get a decrease in flow which can mean an increase in CO2 build up and drop in pH. It could also certainly result in the nitrate increase...keeping filters properly cleaned is critical. You will probably need water changes to get the nitrate down, but hopefully the pH will stabilize soon if that was the problem

 

[tizzo]

Yep... that could very well be the reason. If you removed all the filter media then you removed the beneficial bacteria with it and cause a mini cycle... It is better to remove it a little at a time.
Ophiura got to it first...

 

[okiefish]

Originally Posted by Tizzo
Yep... that could very well be the reason. If you removed all the filter media then you removed the beneficial bacteria with it and cause a mini cycle... It is better to remove it a little at a time.
Ophiura got to it first...
Thanks for the replys guys.
I was concerned about the bacteria as well. I changed 4 foam pads this time. Left the carbon pad and my pre filter media alone. Hopefully things will get better.