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Ammonia and nitrate problems

Subject: Ammonia and nitrate problems
by Yanyan on 12/2/2020 10:52:29

I'm a newbie fish owner, having got a Fluval roma 125 with the u3 filter system over xmas. I set it up on 6th Jan with just plants, filter and air bubble machine, then added 6 neon tetras and a male gourami on 14th, 3 dwarf female gouramis and 3 mollies on 22nd, 2 swordtails on 23rd, and 3 albino corydoras plus a shrimp on 8th Feb, to try and help with ongoing issues! I now know I added the fish too fast at the start, relying on the pet shop staff for advice 🙄

I was advised by the pet shop on 26th Jan to use antibiotics as it seemed like I'd bought infected dwarf gouramis on 22nd, (one had to be put down a week after purchase, after hiding for days, then gasping at top of tank, another has what they said looked like a tumor) so added Interpret anti internal bacteria to the tank on 26th and 30th Jan as per instructions.

I thought the tank was cycled around mid Jan, but on 4th Feb discovered a 0.5ppm ammonia reading. But that was the first ammonia test I did, so am now not so sure. I started doing 30% water changes every couple of days to reduce the ammonia, which lowered the ammonia to .10 by 10th Feb, but it sent the previously relatively stable (but slightly high between .10 to .30ppm) nitrates into 30-50ppm. I tested the tap water and found it to be 50ppm nitrate, so for a few days haven't done a water change. The nitrate is still high at .35ppm, and the ammonia is now back up at .50ppm again. None of which is great and the gouramis just don't seem happy. They spend a lot of time lazing around, especially lower in the tank, they're not as shiny, their fins are starting to look raggedy, their eyes dull. The Tetras and Mollies seem unphased, the swordtails only slightly less active than normal, and one of the corydoras, I've checked several times to see if he moves at all (he has very short bursts of energy, then stops for really long rests), while the other 2 corydoas seem fine.

Bottled water really isn't a viable option, since I don't drive, and 40 litres of water several miles on a bike each week just isn't possible!!

I've looked into pozzani nitrate filters (does anyone have experience of these?) and have a load more plants arriving today to try and lower the nitrates. I vacuum the gravel weekly and keep the tank as clean as I can, and all food given to the fish, once daily, is eaten within about 3 minutes. I wash the filter monthly in removed tank water. But I have run out of ideas on how to get both the ammonia AND the nitrates down, permanently. I'm really hoping someone here can advise me!

Will the fish recover from whatever harm this toxic water is doing them? 😥

All the other readings are fine, the ph is a fairly consistent 7.2, chlorine 0, temp 77 degrees.
Thank you so much