Water changes and fish loss...

[Daniecon]

3 weeks ago this sunday I bought a second hand Osaka 75g, fluval 405, elite 300w submersible heater. Everything was up and running with 2 8" plecos and 2 huge oscars in it. (I didn't take the oscars, they had hole in the head)

We kept everything wet on the 20 minute drive to our house and set it up with the plecos, the next day we bought 5 platys and put them in along with 2 blue 3 spot gouramis.

after a week i did a 25g water change and added 5 red tailed sharks, the following week I did another 25 gallon water change and decided to clean out hte filter. IT WAS DISGUSTING! the everything was clogged with the grossest brown crud, I've never seen anything like it, I had to wash it in city water because there wasnt enough tank water in the world to clean that haha.

A few days after this I lost my first platy... this happened after my heater broke and it was cold for a day so i though maybe the 20 degree celcius water killed it.

I then added 5 tiger barbs on Monday and did another 25g water change tuesday. Today I woke up to 2 more dead platys.

I`m wondering what may have caused my platys to die, is my tank cycling where I cleaned out the filter, are the other fish harassing them? Stress from frequent water changes?

none of the other fish are showing any signs of illness, and I know the platys have no place in this tank, i only bought them to cycle the tank a bit and to provide fry for the other fish to eat. I also plan to get rid of one pleco and i'm trying to convince hubby to let me get rid of 4 of the 5 sharks, but he bought em and he likes them

[imma24]

We kept everything wet on the 20 minute drive to our house and set it up with the plecos, the next day we bought 5 platys and put them in along with 2 blue 3 spot gouramis.

after a week i did a 25g water change and added 5 red tailed sharks, the following week I did another 25 gallon water change and decided to clean out hte filter. IT WAS DISGUSTING! the everything was clogged with the grossest brown crud, I've never seen anything like it, I had to wash it in city water because there wasnt enough tank water in the world to clean that haha.

A few days after this I lost my first platy... this happened after my heater broke and it was cold for a day so i though maybe the 20 degree celcius water killed it.

I then added 5 tiger barbs on Monday and did another 25g water change tuesday. Today I woke up to 2 more dead platys.

I`m wondering what may have caused my platys to die, is my tank cycling where I cleaned out the filter, are the other fish harassing them? Stress from frequent water changes?

none of the other fish are showing any signs of illness, and I know the platys have no place in this tank, i only bought them to cycle the tank a bit and to provide fry for the other fish to eat. I also plan to get rid of one pleco and i'm trying to convince hubby to let me get rid of 4 of the 5 sharks, but he bought em and he likes them

Ok - do you have a test kit to know what your water parameters are?

It sounds like you added waaaay too many fish at one time. A 75gal tank will not hold an unlimited # of fish. You need to be sure your water parameters are good (using a liquid test kit for accuracy) before adding new fish and then see you have 0 ammonia before adding more fish to make sure your filter is handling the additional ammonia well. Plus, I'm guessing those fish are totally not compatible with each other anyway. I believe the sharks need to be alone (meaning only 1 in a tank) and are very aggressive/territorial. Tiger barbs, from what I've read here need to be in a tank by themselves (due to their aggressiveness as well). If you have common plecos, they will also get too big for your tank.

Did you clean the filter media in the water using dechlorinator? If not, you most probably killed all the beneficial bacteria. What are you using as dechlorinator when you change the water?

It is also possible that a drop in water temp affected your fish as well - hope you've sinced replaced the heater.

[Daniecon]

I used an aquarium calculator to determine if my fish will be ok in the tank, and they will once I get rid of the pleco(s) and some of the sharks since they will fight when they get bigger, i also used a compatibility guide to stock and the barbs are fine with the sharks and gourami. The only fish I have that don't really work are the platys.

I'm using nutrifin aquaplus to dechorinate my water for water changes and am using cycle... which I know doesn't do much, but it was given to me and wont hurt so I use it. I replaced my heater the day after it stopped working, and I'll pick up a test kit this weekend to see if all is ok.

All the fish except the platys are behaving normally, which leads me to believe they're being harassed because besides the plecos they are the hardiest fish in the tank.

[Cermet]

I think you lost your bacteria in the filter when you cleaned it in chlorinated tap water - if you measure your tank water parameters (ammonia, and nitrite) I would think that you have ammonia at unhealthy levels. Check this out and if so, do a large water change and get some ammonia absorber (or just do daily large water changes as needed to keep levels below 0.5 ppm.) You will see dangerous nitrite levels at some point if the filter is cycling again - could takes weeks.

An aside: when ever you lose fish, always do at least a 50% water change after measuring water parameters even if these parameters measure zero. Fish die for a lot of reasons due to water issues but clean water can fix a lot of possible problems. Larger water changes are even better.

In my opinion, no matter how dirty the filter, never use chlorinated tap water - rinse out what you can with old tank water and put the filter back - they can be very dirty and will work like a charm (as long as water still flows.) Sounds more like you need a second filter and might be feeding too much (my canister with five massive discus never builds up any significant gunk at all.)

Best of luck.

[imma24]

Yes, the test kit is extremely important considering how many fish you have in there and how quickly they were added.

When people post here asking about how to stock their tanks, the usual recommendation is to add a few, wait a week or two for the filter to grow enough bacteria to handle them and then add a few more until stocked.

If you want a really good dechlorinator, get Prime - most members use it and it's very cost effective - you don't need much - 1 capful for every 50gal versus other brands that require twice that amount.

Hope you used dechlorinator when you cleaned your media. My media also gets pretty gunky and sometimes I use 2-3 buckets of tank water to do that.

You might also want to look into getting a 2nd filter for that tank - in general its better to have enough filtration for double the size of the tank - so in your case for 150gal - it'll keep your filters much cleaner and you will have a backup filter in case one of them fails. This will also help you keep your water parameters good - too little filtration might show up in elevated ammonia/nitrates with all those fish you have in there.

[Daniecon]

Sounds more like you need a second filter and might be feeding too much (my canister with five massive discus never builds up any significant gunk at all.)

The filter wasn't cleaned from when I bought it second hand... I didn't want to so I could kep the cycle going, The guy had 2 GIANT oscars in there, both with HITH so I'm thinking he didn't clean it much. The gravel was so dirty that the water was black after my first water change.

As it stands I did a 25% wc and will continue to do that daily until I can get that test kit and I'll work my way from there. My project for this weekend is a DIY python because all this bucket lugging is killing me.

[ryann]

Just make sure if your going to use fresh water to clean your tank you be sure to dechlorinate your water first. The chlorine will kill any beneficial bacteria you have and your most likely going through another cycle.

[JoeE]

Just a friendly heads-up on the DIY python - you can certainly do it economically with a normal garden hose and get a perfectly functional python, but if you want to use clear beverage hose it will be quite a bit more expensive to the point where you won't really save a whole lot compared to just buying a out-of-the-box one from the store. It really comes down to personal preference - I strongly prefer the clear hose so I can see what's going on inside the python in case I accidentally suck up a fish or it gets clogged.

[pjaldave]

Fish you have are somewhat not compatible with each other.

Multiple gourami in same tank, wrong. They will harass each other to death, the dominant will live, the other will always hide or just die.

5 red tailed sharks in the same tank, wrong again. They are territorial and very aggressive towards the same specie, I only recommend having one if you really want them. But I would really advise not to have them right now.

Tiger barbs are known nippers, notorious they are. I wouldn't put any long-finned species with them. Gourami might not be a suitable idea for tank mate. Upping the school might help with the nipping.

Platies are peaceful fish, and from your stock, you have a semi-aggressive setup. And that's why your platies are dying, besides the point that your tank is cycling.

After all that i've said, you need to cycle the tank completely first before adding any more species. And, you need to do larger water changes than 25% when you are cycling.

[Goes to 11!]

+1 to the stocking tips.

Imo you should have cleaned the gravel before adding the fish. Considering the state of the tank, Much nastiness was released when you opened up that can of worms by disturbing it.

Secondly I agree that you added too many fish at once and when you add to that the loss of your BB by tapwatercide this is a perfect storm.

You are now cycling with fish, Prepare for water changes to keep your Ammonia and 'Trites from getting toxic.