New Tank, Fish Dying

[Phillysailor]

Howdy
 
I've a new, planted plywood/epoxy 63 gal tank just built which has three filters, turning over the water 8 times through internal canister filters and a water polisher/heater box with filter floss. That box also has a bubble stone, which provides for surface agitation above. I'm always seeing very small bubbles in the water, too. The cycle went well, took about 5 weeks, and now my ammonia is 0, nitrites are 0, Nitrates 20-40, GH is 40 and pH is 7.2. Substrate is Eco Planted complete (3 bags). Temp is 77-78 deg F (2 300W heaters). There are three good size Mopani driftwood, modest planting (10 plants, still small) providing some cover. Two lights on a timer strip provide night (16hrs) and day (8.5hr) cycle. Algae growth is minimal, and I've tossed a few snails.
 
Occupants:
 4 Cory, (2 Peppered, 2 skunk)
 2 Albino Cory
 5 Red eye swordtail
 4 Black skirt Tetras
 12 Cardinal Tetras
 1 Red Tail Shark
 
 
Recently, there have been numerous deaths... 7 of 8 Cardinal Tetras and both of two Peppered Corys from the LFS within a week of purchase. I went back and replaced numerous fish, leading to the above stock. But tonight, one of the Albino Corys died, and the other is now lethargic (but vigorous enough to escape the net). All fish except the 4 black skirt tetras are from the same LFS.
 
My water is good tap water through a three stage filter which is advertised to remove all Chlorine and Chloramines, and most other contaminants. I do 10-20% water changes 1x per week, after which I add 2-3 caps Flourish. 
 
Should I avoid the LFS? They seem reputable, and replaced my fish after asking to see my water tests. I did note three dead fish in the tank from which I'd received my doomed Cardinal tetras, but they were down in the substrate and I was told it was a fragile species.
 
Should I do further testing of the water, and what should I look for? I think there is plenty of O2 in the water, as all the fish seem quite active (except the dying albino C) and don't hang at the surface too long. 

 

[BaylorPerez]

well, first off is there any clouding in the water, as this could be a bacterial thing, or from as it sounds their is over crowding, the general rule is 1inch(for the fish) is 1 gallon of tank that they need, and as you have several fish that grow to 4+inches, it could just be because of that. Also, do you feed them any of them different foods?.
 
 
When replacing the fish did you wait a couple days to see if any more have died, as well as do you acclimate them 15-30 Mins, no more than 45 mins.
 
your nitrates may want to be brought down to below 10 as that may be causing some of the lethargy. 
 
What filters are there that you use? having 3 is maybe to much water flow, but to much is also good as it prevents bacteria blooms.
 
has the tank been setup within the past week or is this built today?

and tetras are hardy fish, not much can kill one as what ive seen with my tank. so im shocked that many have died

Editt --- when doing water changes change 30-40% to help with the low Ammonia and nitrite levels

 

[Phillysailor]

Acclimation: 15 minutes in the bag, then 10 minutes with some tank water let in. 
 
Water: crystal clear. There are two canister type filters (in a 4" PVC pipe) with one run by a Maxijet 1200 and one a Maxijet 600. One pumps into a grid of PVC in the substrate, the other creates flow in the tank... across the back (quite strong). The fish avoid it by hanging out in the other 85% of the tank. There is a mixture of mechanical and biologic media in each.  The third filter is just filter floss with a MaxiJet400 for cleaning the water.
 
The tank was cycled (5 weeks) before adding fish. By the end, one day after adding 7 ml of 10% ammonia the ammonia was 0 and nitrites low.
 
First stock of fish (5 cardinal tetras, two cory and five swordtails) are all still alive. They were introduced three weeks ago. The die off was with the second batch of fish added last week. By my estimation I have no more than 30 inches of fish in a 60 gallon tank, and a third of those "inches" are cardinal tetras, which hardly seems fair.

 

[Jeremy180]

The fatal flaw of the "inch per gallon rule, is that it assumes fish are one dimensional beings.
Obviously, they are not.
Take for example, for two otherwise identical fish, one being one inch and the other being four inches.
The four inch does not weigh four times as much as the one inch fish, but 4x4x4=64 times as much, with a corresponding increase in bioload.

 

[BaylorPerez]

yea i dont normally follow the rule but in a 20Gal tank i have 11 fish(9 actual fish and 2 snails) so im alittle overstocked by the 1inch=1gal rule. but my fish havent died yet. so im happy with my 11 fish.
 
yet i dont seem to understand why your fish are dying by the size of your fish. but for a 63 gal tank you have about 30(give or take) average fish in their at one time if im correct?
 
so maybe its your water, are their any heavy metals that your water supplier adds to the water in which you used?

 

[NickAu]

 
10-20% water changes 1x per week

IMO that is not enough water changed.
 
Re this tank of yours I suspect it is leeching chemicals.
 

 
My water is good tap water through a three stage filter

Please give more details, Is this like an RO unit?

 

[Far_King]

Ammonia , Nitrate and Nitrite all sound fine.  I'd not worry that your Nitrate is 20-40.  Chances are you'll not be able to get it lower as that's what your water may naturally be.  See this thread for more on Nitrate http/www.fishforums.net/index.php?/topic/440148-the-nitrate-debate/
 
As Nick has suggested, if you're using RO or some sort of filtered water you may be removing essential minerals from it that means it can be toxic to the fish unless re-mineralised.

 

[Phillysailor]

It's not RO, it's a good three stage water filter, like those used for an ice maker. APEX MR-2030 
 

• Stage 1- 1 micron polypropylene sediment pre-filter to extract suspended materials such as sediment, rust, insects, and other particles down to 5 micron. (Replace every 6-8 months)
• Stage 2 - Carbon block filters to absorb heavy chlorine byproducts such as chloramines, THM, and TCE. The double carbon briquettes filter out organic matter from water without release of carbon fines. (Replace every year)
• Stage 3 - Carbon block filters to absorb heavy chlorine byproducts such as chloramines, THM, and TCE. The double carbon briquettes filter out organic matter from water without release of carbon fines. (Replace every year)

 
Should I be testing something, or adding metals? This tank has only been going three weeks or so, and the second batch of fish all died within a week, or a week and a half. Hard to believe fish die because of lack of heavy metals in that short period. I am adding Flourish Excel after water changes: does that add minerals? 
 
Leaching chemicals? Hmmm. Used MAS epoxy, which is non-toxic once fully cured. OK for eating surfaces, for instance. But the paint... Krylon spray paint. 99% of it was fine, but some of it used on PVC did flake. I think that happened mostly during the cycle, but.... 
 
To be honest, that's my biggest worry. 
 
What I am clinging to is that the first fish added have all done fine. It was the second batch of Cardinal tetras (which was from a LFS tank with 3 dead fish, common filter with the two Corys which died) which was decimated. Since then, one albino Cory, one on deathbed. I just dunno.

 

[Jeremy180]

 

 
10-20% water changes 1x per week

IMO that is not enough water changed.
 
Re this tank of yours I suspect it is leeching chemicals.
 

 
My water is good tap water through a three stage filter

Please give more details, Is this like an RO unit?
 


I'll second this, and third it too if I could.
A properly stocked tank needs about 50% of the water changed at a time, more than once a week if you're heavily stocked.

It's not RO, it's a good three stage water filter, like those used for an ice maker. APEX MR-2030 
 

• Stage 1- 1 micron polypropylene sediment pre-filter to extract suspended materials such as sediment, rust, insects, and other particles down to 5 micron. (Replace every 6-8 months)
• Stage 2 - Carbon block filters to absorb heavy chlorine byproducts such as chloramines, THM, and TCE. The double carbon briquettes filter out organic matter from water without release of carbon fines. (Replace every year)
• Stage 3 - Carbon block filters to absorb heavy chlorine byproducts such as chloramines, THM, and TCE. The double carbon briquettes filter out organic matter from water without release of carbon fines. (Replace every year)

 
Should I be testing something, or adding metals? This tank has only been going three weeks or so, and the second batch of fish all died within a week, or a week and a half. Hard to believe fish die because of lack of heavy metals in that short period. I am adding Flourish Excel after water changes: does that add minerals? 
 
Leaching chemicals? Hmmm. Used MAS epoxy, which is non-toxic once fully cured. OK for eating surfaces, for instance. But the paint... Krylon spray paint. 99% of it was fine, but some of it used on PVC did flake. I think that happened mostly during the cycle, but.... 
 
To be honest, that's my biggest worry. 
 
What I am clinging to is that the first fish added have all done fine. It was the second batch of Cardinal tetras (which was from a LFS tank with 3 dead fish, common filter with the two Corys which died) which was decimated. Since then, one albino Cory, one on deathbed. I just dunno.

These are known to be more sensitive to chemical contaminants, and if the spray paint flaked, that might mean it wasn't properly cured.
Not saying for sure that this is your problem, but it raises a red flag for me.

 

[Phillysailor]

Glad to report that all fish, including the sluggish albino Cory, are doing well. I've increased the frequency of water changes, but everything else is the same. Great activity, and thanks for all those who took a moment to respond. 
 
I think I got a bad batch of fish.