another dead fish

[friedegg45]

this is the third fish in two weeks i have lost not doing anything different. 2 platys and now a tetra but seems to be when i feed my pleco his food tablets. the water parameters are gh 120,kh 40, ph 7.0,no2 0, no3 80, any advice cheers troops

[eve]

sorry about your loss


WOW

you have got some high nitrAtes going on there
optimal it should be around below 20ppm
around 40is is still acceptable

but 80, is way off !!!

thats where your problem lies


when did you do your last waterchange and how much?
how often are you doing water changes?

what are the nitrAtes from your water source?


any plants in the tank?
if yes, are you using Co2 or fertilizers?

[friedegg45]

water change once a week 20/40% live plants but no fertilizer or food for them what do you suggest last change was thursday do you think i should maybe do one tonite say 20% cheers

[eve]

yes, i would definitely do a 20% waterchange today, but make sure the water source is lower on nitrAtes then your tank is currently

repeat water changes every 2-3 days, 20% until you get control of your nitrAtes

that should help your fish immense

also rinse out the filter cartridge, and do a really good gravel vacuum

[jonv]

Well there's different approaches by everyone when fish start dying. I'd do just like Eve said and first I'd start looking at my water. I see the 80 in nitrates and makes me wonder too. From my understanding of nitrates though, death from that alone is over time and more like a prolonged exposure to it. Now if we figure they've been in that water say six months, that's certainly some prolonged exposure.

When I see high nitrate readings, yet people are doing weekly water changes, a couple things pop into my head. First thing I want to know is the volume. Maybe increasing the volume of the change will keep the daily rates the fish are exposed to it lower? Maybe try going up to 40-50% weekly. Now I have also seen on answers, where I suggested testing the tap water source found this to be the real culprit. Your tap water source may just as well be already high in nitrates. You find this in many cases where you are located in a rural area type and there are either golf courses or farms nearby causing nitrate run off. Checking your your tap water is worth your time to make sure that's not putting nitrates back in.

Overall health also effects the rate at which fish would get afflicted by nitrates. I see your KH looks ok but maybe if you boost that with something like wonder shells, the increased calcium and magnesium can improve your redox and give a boost to your stock. You might want to consider giving your stock a meth blue bath. My work with this came from Carl pointing out how it boosts oxygenation absorbing and reduces the effects of nitrite and nitrates in the blood too.

What sized filter is this and tank? This might also be a case of too much stock in a tank too small. You put just the right sized filter in there, and the turn over of nitrates back into the tank make this a case where your return level to too high of nitrate levels makes you have to change the water much sooner. Increasing your tank size or maybe your filter size might assist with this or lower your stock level. Hard to tell though without knowing the tank size and your filter.

[goldenpuon]

What is yoru ammonia? That could also be high if the nitrates are up even though you said your nitrites were at 0.

[Carl]

I am late to this tread, but will basically back up what others have said.

Start with checking parameters as you have done, then it was already noted that your nitrates are high, however as noted by Bill that high nitrates generally kill in the long haul and even then via lowering immunty to the fish, so once you take care of your nitrate problem, you still may have a disease problem that the nitrates allowed to establish since many aquatic pathogens are opportunistic and only attack when resistance is down for whatever reason.

Once this problem is rectified you may need to add a treatment or look at other possiblities as this is a case where you start "knocking down" each problem, then if that does not soilve it move to the next possibility.

I will also point out that although 80 ppm is a high nitrate, this alone can only cause stress ona fish that allows for other problems to kill, as studies have shown that actual fatal harm does not occur until 100 to 200 ppm depending on the species.

Here is the Aquarium Answers article on Nitrates:
Aquarium Answers; Nitrates

Carl