Cant Keep My Nitrate Level Down!!

Hi, as in title, i do 50% water changes weekly. last one i did was on friday there and i decided to check my nitrate tonight (monday) and its 50 ppm! when i changed the water on friday i done a bigger change than usual and had my nitrate down to 10ppm, so ive gained 40 in 3 days!

im using test strips for my nitrate as i wasnt getting accurate readings with the drop kit.

my tank is 200 litre, i recently added 4 (2.5") discus to the tank so have been feeding them beef heart 3 times a day as this is what i was advised to do when i bought them. my tank is at 100% on the community creator with 4 clown loaches 4 discus 2 silver dollars 1 male guppy 2 black molly's  a golden nugget plec 1 bristle nosed plec 5 xray tetras 2 male swordtails 5 otocinclus 8 julli corys 1 peacock goby 4 female swordtails and 5 indian gouramis.

ive recently upgraded to an all pond solutions 1400+ litre ph filter and am running it in beside my fluval 304 filter till its run in and i plan on selling the fluval one. i also have seachem matrix in the filter to help out.

ive got 3 plants in the tank as well. how do i try n keep my nitrate level down?  do i need more plants and maybe a big bit of bog wood? i cant understand why im getting so much nitrate.

any advice is much appreciated!

-Dylan.

You could try cutting back on the food, you may be over feeding them. That seems a heck of a lot of fish though, even with the external filters and even though the CC has you at just 100%. Lots of fish=lots of poop and that gets broken down to nitrites and then and then nitrates. So even though your bacteria is coping with the ammonia and nitrites, the end result will be large amounts of nitrates.

Unless anyone has a better idea of the cause.

edited to add: same theory as Sue I guess

Yes. Decomposing cucumber -> ammonia -> nitrite -> nitrate.
It can also make the water cloudy.



Courgette is more nutritious than cucumber 

ive recently upgraded to an all pond solutions 1400+ litre ph filter and am running it in beside my fluval 304 filter till its run in and i plan on selling the fluval one. i also have seachem matrix in the filter to help out.

Hmmm... How recently? You mention you tested for nitrate but do you also test pH, Ammonia and nitrite?

It's the same for courgette - remove any uneaten bits after 12 hours.