Plecos keep dying :(

[Coleallensmom]

Originally Posted by mickitiffen

Water parameters have tested normal, no ammonia present, nitrites(3), nitrate(40)

How long has this tank been running? Those water parameters are NOT normal for a cycled tank. An established tank should not have any nitrite reading; especially not one that high. If it is an established tank, then how often are you doing maintenance? 1x Weekly PWCs go a long way towards keeping your tank/fish healthy.

If this is a newly setup tank, we are in a whole different ball game. When still in the cycling process, those daily water changes you spoke of can be very important but sometimes it becomes necessary to do more than one PWC a day to control the spikes in ammonia and nitrIte that happen along the course of a cycle. The reason the previous posters have recommended doing several emergency PWCs is because of your high nitrite reading. Anything over .25ppm of ammonia or nitrite can be harmful to your fish, so you can just imagine what the 3ppm reading is doing to them. If you leave it that high, you will experience more fish deaths...hence the recommended extra PWCs. Amquel/Prime may help detoxify nitrite but fresh water is the only good way to get those levels lower. For that very reason, make sure you are doing no less then 50% PWC's while still cycling.

[mickitiffen]

I realize that but I have heard that too much of that will stress the fish as well.

[mickitiffen]

This tank has been going for about 8 years. My husband had this hobby and he died in 2007. I did clean out the filter almost completely removing water--wd that have an effect. I typically changed the water 40/50 % 1x month and replenished as needed.

[Tim Wheatley]

Don't worry, whatever happens please continue the hobby as I'm sure it brings you memories.

In any case, cleaning the filter out completely can kill off the bacteria which keep the tank cycled. it doesn't seem like it recovered yet.

[mickitiffen]

I am doing my best. someone I know who is a fish keeper said he wondered if the cory catfish were beating up the plecos.

[Coleallensmom]

Sorry to hear about your husband. We are all here to help if you have questions. If your tank has been set up for several years, then it should be well established and passed the cycling stage. How did you clean the filter? Most of the good bacteria in your tank lives in your substrate and your filter materials. While you many need to occasionally change your Eheim pre-filter/fine filter pad, most Filter materials should not be replaced unless they are falling apart but can be rinsed with old tank water. As long as all the media is kept wet, it is possible to clean all your media thouroughly without making any huge effect on the bacteria living there. Whether your current nitrite spike is from the filter cleaning or not, I would really advise stepping up your regular maintenance schedule. Many recommend doing 1x weekly 25-50% PWCs to keep you water parameters in check.

[Coleallensmom]

Originally Posted by mickitiffen

I am doing my best. someone I know who is a fish keeper said he wondered if the cory catfish were beating up the plecos.

I can't imagine that the cories are bothering the plecos. If you have plenty of alage for the plecos to eat, then there shouldn't be a problem. Step up your maintenance schedule; I wouldn't be surprised at all if that were the issue. Even if ammonia and nitrite are at 0ppm in an established tank, nitrates can still be present and get to high enough levels to affect the fish. Regular PWCs keep those nitrates in check. While <40ppm is acceptable for nitrates, <20 is ideal.

[mickitiffen]

to clean the filter I replaced the white pad. Just added carbon to it the second level, cleaned the prefilter and emptied most of the water (myb that was a mistake--I hear it both ways). I changed the water 2x today and used Amquel consecutively 1x a day.

[mickitiffen]

To tell you the truth, my husband was not that diligent about water changes, myb 1x mo or less. I have heard people go both ways. I never remember him cleaning the filter either. He was bio/earth science teacher for many years and knew his stuff.

[Tim Wheatley]

Often cleaning the filter too much can remove the good bacteria and before it has time to regrow the levels in the tank can spike and kill fish. That actually sounds the most likely issue you may have had now. It depends how you clean the filter, and which bits you clean. For example when rinsing always use water from the tank, rather than tap water as the chlorine in the tap water is what kills the bacteria.

[mickitiffen]

When you say to rinse in tank water do you mean the water in the tank itself? The Eheim is a 3 part filter. I was told to replace the white pad when very soiled. Are you saying to rinse it out instead in the tank?

[Tim Wheatley]

When you do a water change keep some of the water you have taken from the tank and rinse in that. Basically just remove the gunk so the water isn't impeded through the filter.

Some people never replace their filter media, this was probably the trick with your husband. The tank water is safe to the bacteria on the media, removing the gunk while rinsing in tank water should not kill the bacteria present, while using tap water probably will.

[Coleallensmom]

Originally Posted by mickitiffen

To tell you the truth, my husband was not that diligent about water changes, myb 1x mo or less. I have heard people go both ways. I never remember him cleaning the filter either. He was bio/earth science teacher for many years and knew his stuff.

Cleaning the filter isn't something the needs done weekly. However, I'm sure your fish would thank you if you changed the water more often then 1x every month or two. I hope that you at least test the water and keep track of your nitrates.

[mickitiffen]

Thanks Tim. I will try to remember that

[mickitiffen]

Nitrate and Nitrite were both zero or .5 tonight! so glad down. I have been worried about my ghost knife who seemed to be breathing fast and swimming vertically last night. Today he has been very active and ate all his blood worms. I did notice a grey discoloration on him, almost like a spider web in one spot. Is that something to be concerned about? Doesn't look like ich. He is about 5, not sure how long they live.