Fish Deaths (help Please)

[ceejay123]

Hello there.
I hope any answers to this post will help me in the future as over the past four months I have lost several fish and I am getting pissed off, not so much about the expense but more about my perceived lack of care for the fish I should be looking after properly.
I am not inexperienced in keeping tropicals but have been, until June, away from the hobby for several years, 17 in fact.
I bought a 30 gal Juwel tank with internal filter etc in June and after 3 weeks started to introduce fish.
I religiously do a 1/4 to 1/3 water change less than 10 days apart. I siphon using a piece of dedicated garden hose which really pulls the crap up off the gravel. I stop the flow and disturb the gravel from time to time then suck up the crap.
I rearrange the plants and tidy things up at this time also using a "green scouring pad" to clean the glass but not the rear glass. When I refill I do not add chemicals to act against the chlorine and do not attempt to get the temperature exact as I think the fish enjoy an infusion of slightly colder water( I do warm up the cold tap water with kettle water).
I clean the Juwel filter medium regularly in siphoned tank water, So I think I try to create and maintain a healthy environment for the fish...BUT
To my horror over the past four months I have lost after initially seeming to thrive, 1Pleco 2 Honey Gouramis several Neons 2 male Guppies 2 female Guppies 1 mountain Shrimp and today the Red Tailed Black Shark succumbed after weeks of watching it shrink and become mis-shapen. I had a pair of Honey Gouramis and one of them died then after about 3 weeks it,s replacement actually disappeared altogether!! Its replacement was bullied to death in just one evening by the remaining male who is now the saddest loneliest fish i have.
On a brighter note there are successes in the tank!!
The 10 Harlequins I've had since July are brill' as are the 3 Angels 2 Speckled Mollies 4 Danios 5 Black Phantom Tetras.
Today I removed the piece of shop bought "bog wood" thinking that that might be contributing to the ill-health and as I type I have rang the Wife to ask her to get some de-chlorinator from the fish shop. I have never ever used chemicals but if the consensus Is that chlorine is the fault then I'll give it a try.
Meanwhile I'll soldier on, making the Aquarium shop owner even richer in the process, 'till i get it right.
Chris

 

[Meds081603]

Well of course the water stats are needed to determine if things are ok. Did you add all the fish at once? Slightly cooler water is fine but you really don't want a big swing in water temps. Dechlorinating chemicals really are a good thing to add unless you are aging your water. Lastly it sounds like that tank is incredibly overstocked. If you had that many fish die and still have 10 Harlequins 3 Angels 2 Speckled Mollies 4 Danios 5 Black Phantom Tetras than that is waaaay to many fish for a 30gallon tank.

 

[ceejay123]

No the fish were added gradually a couple at a time and so on. One of the Angels is starting to act differently from the other two. Its gone low down and is staying among the base of the plants.
I know it sounds a lot but I don't think it is. There are 12neons 5 phantoms 10 harlequins 2 mollies 2 guppies 2 4 danios platties 3 angels and a (new) Plec making 41 fish in all. But all bar5 are quite small and the tank does not feel to be overstocked to me.
My wife came home with A P I Stress Coat conditioner. Not used it yet. Does anyone know anything of this product.
Chris

 

[demonmagus]

lol might have to resize your sig 0_o

 

[ceejay123]

lol might have to resize your sig 0_o

I wish I knew how to do this. I put some relevant pics in photobucket and eventually got this lovely pic of my friend the Speckled Molly to move as my sig' but it's this size!!!
Chris

 

[Polenth]

I think it would be overly hasty to assume chlorine is the only problem as you haven't checked the water quality. You won't really know if your tank is overstocked (from the bioload point of view) unless you test the water. Liquid test kits are usually recommended for being more accurate. You should have 0 ammonia, 0 nitrite and some nitrates.

Still use the dechlorinator though, as chlorine will kill fish. The best way is to treat the water before you add it, following the dosage instructions on the bottle. They're very safe products. You won't accidently kill your fish with an overdose or anything like that. Most them also deal with heavy metals and chloramine - you can't get rid of those by aging the water.