Poor water, stressed fish, need advice

[rjdoghouse]

I'm having a terrible time with my tank - the water is way off and I haven't been able to add fish for a few months. Over this time, still not much improvement.

I have a 20 gallon tank which currently houses
1 swordtail female
1 neon
5 zebra danios
3 cory cats

There used to be a couple more fish, but they are gone. Currently I have the swordtail experiencing what appears to be popeye - with one eye cloudy.

I have the following test readings - using the 5 in 1 test strips from Marcel. With the same readings at the petstore on what this one covers, I was also told the ammonia was not high - but my nitrate was way over. Basically they told me to do water changes every two weeks and use a product called Prime which says it will detoxify the nitrate/nitrite and remove the chloramine,ammonia and chlorine

My nitrate tests somewhere between 80 and 200 ppm (it's in between in colour about halfway to the darkest colour, so it's very high - perhaps 140 or so?

nitrite 0 or very close to it

total hardness 120 ppm

alkalinity/buffering capacity 100ppm

ph is approx 6.8 - slightly darker in colour, so perhaps 6.9/7 (next level on the test guide is 7.2 and it's not quite that colour)

I had put some melafix in the water the last couple of days for the swordfish as I wanted to use something more natural rather than add more chemicals and I have been using double doses of PRIME in order to try to lower the nitrate levels.

I had green algae all over the glass and I've used a scouring pad (clean plastic type, no detergents) to scrub it off this evening. I think that might alter the water tests for the worse in the next few days

The test strips and test results are pretty constant, although the nitrate has dipped a little lower - not much though. I will say I've not been constant with the water changes and I'm working on that. Last changed 7 days ago - approximately 10-15% using a gravel vacuum. I had done it 14 days prior as per the direction of the petshop. They said every two weeks - but I wanted to clean it up a bit as I was rearranging the tank and new it would stir up waste in the gravel.

My gravel might be a bit thin - I use an aqua filter, no undergravel one - and the gravel is only about 1" deep - perhaps less. I changed the filter pad about 3 or so weeks ago and the carbon probably 2 months - they were both in desperate need, but I knew not to do them both at the same time. This past week with the water change, I squeezed the sponge clean in some treated water (using the water conditioning formula and letting it sit before I swished the filter sponge in it to remove some gunk from it.) I didn't clean it right out, just the heavy gunk trapped in the bottom.

Oh, and my tank has been running for a few years. It was my sisters and we rolled it down to my place, so it hasn't really been altered much in that time.

This problem started quite some time ago - lost fish and won't replace until I get it right. I could really use some advice on how to correct this problem - I want to make it work and have a beautiful aquarium with a couple more tetras and another swordtail or two. Those singles in there could use the company I'm sure.
So your advise is most most needed and appreciated!

I also really don't want to lose my swordtail or any of the other fish, who must all be very stressed.

 

[ajhainey]

Have you tested your tap water? Could be its already high nitrate even before you add it to the tank...

If ammonia and nitrite are very low->0 and the tank has been running a awhile then its sounds like you are cycled and aren't suffering a mini cycle or anything. Also the ph looks good (to my inexperienced eyes) so it seems like its just a nitrate problem; that means the gravel/filter changes are probably not an issue (problems there would give you a nitrite or ammoni spike) - and its all down to plant balance/water source/water changes....It also means you don't need any 'fixing' products they tend to be aimed at ammonia/nitrite not nitrate.

My first guess is your tap water is high nitrate itself, your only choice there is to find a source of cleaner water (see many other threads on this around here). RO from your LFS maybe, or get a nitrate filter.

If the tap water is ok, up the water changes until you see a change. Up to about 30% a day never seems to do my fish any harm when trying to 'recover' from a crisis.

The final option is to add live plants, they feed on nitrate so should help lower levels..however I find the effect rather slow and not that big. Also green algae is feeding on the high nitrate - adding more plants might help out compete it. Finally put the lights on for less time (8 hours a day?) and make sure the tanks not in direct sunlight to help slow the algae down...

I think thats everything - Good Luck!

aj xx