Heavy metals in aquarium? Best way to remove?
Hi! I'm new to planted tanks and what got me into it was the idea of turning this small 5 gallon bowl into a paradise for snails and red cherry shrimp. However, I mistakenly have introduced a lot of heavy metals into the water. I wanted to decorate my bowl with lots of rough stones (mostly quartz's and jade) but I stupidly added some chunks of pyrite. The tank has been going with just plants and snails for about 3 weeks now and a friend pointed out to me that I should remove the pyrite because it would leech heavy metals into my water. Even after a water change, when I did some test strips the GH was 180, way too high for me to even consider adding RCH. I've been looking up ways to safely reduce the heavy metals in the bowl, but everything I've read is about removing them from the tap water before adding it in, which I already do with a water conditioner. Will the metals slowly be removed over time as I do more and more water changes? Or do I have to drain my whole tank and start over? I want to avoid doing that as the bowl has been cycled and the plants look like they are starting to establish a good root system and grow new leaves. Plus my nitrate and nitrite levels have remained safe and stable.
On a side note, the pH of my water is also very high, both probably from the extra metals but it comes out around 7.8 from my tap. I had an air rock bubbler going until I read that adding oxygen ups pH, so that's been turned off. Should I be adding CO2 if the pH is that high? or should I just stick to adding pH down to my tap water that I treat for changes?
Thanks for any help! Sorry if the answers to these questions are obvious but I'm so excited to add shrimp but I want to make sure i'm putting them into the best and safest environment I can provide!