Me again!

[Scrumpy]

Well the fishless cycling allowed me to fully stock at once which worked a treat only I think I'm completely overstocked now. I lost half my cardinals very quickly so I added 8 more using the drip method and they all survived....when I wa santicipating 4.
Now in my 130l tank I have 6 long finned zebra danios who are eating each others tails off, 4 Bosemai rainbow fish, 12 cardinal tetras, 3 otos and 3 peppered cories.
I'm having to do 50% water changes twice a week to keep the nitrates down....after 4 days they're up to 60 ppm. Tap water 25-30 ppm.
I've got some plants in there...hygro polysperma, anubias nana, crypt wendii and hygro limon something.
I'm trying not to overfeed.
Will the nitrates settle down or am i going to spend half my life doing water changes?! What happens when the fish grow? Daily changes :-@
Can anyone tell me how long my fish will live? The danios have made such a mess of each other I won't replace them when they die...or any others.
Any advice please?

 

[luvfishies]

Your nitrates will NOT get any better as time goes on. 30ppm out of the tap is insane!!

There are nitrate reducing pillows available. I'd treat the changewater with a pillow to get nitrates to 0. Do this for a while til the tank nitrates are below 20ppm, and then you may be able to reduce the volume and frequency of the waterchanges.
As long as the tap has HIGH nitrates, though, you're stuck with using the pillows, unfortunately.

 

[Troy-N-Eli]

Just a thought, if you're willing to go to the expense.  We were forced to use bottled water in our tanks.  The tap water was so horrid and hard that after 2 days, the evaporation made the water look like chalk.  We have found that Spring water works best, since distilled water is almost too pure and has no beneficial critters in it that are good for the tank.

Granted, this route can get expensive, especially if you have big tanks and have to do a big water change.  However, if you can't get your levels under control any other way, it is a good quick fix.  It's worked for us and we've had no problems recently.  Hope that helps.