I live in the UK and have a 180l tank, which I have stocked with mainly Malawi and a couple Victoria Cichlids, my current filter set up is a Fluval 205 canister filter. I am having a problem with increasing nitrates in the set up, at least partly down to the tap water I am using for water changes (40% about every 7-10 days) has 40ppm out of the tap.
About 2 months ago I purchased 1l of Seachem Matrix, 1 of DeNitrate and 100ml pouch of Purigen, over the course of the last 2 months I have gradually added the Matrix to my Fluval filter removing the ceramic media that was in there, I am now running about .9l in the Fluval with the Purigen but have not seen an improvement in the nitrate situation.
My question is where do I go from here, will the 1l of DeNitrate I purchased be enough? I have been trying to work out whether to get a new canister filter and put the DeNitrate in my Fluval and reduce the flow or whether to build a custom filter to house the DeNitrate?