Hi all - i'm new to posting on this forum but I've been reading previous posts here for a while ... however i've not come accross a solution for our current problem before so here goes.
First off the disaster (sorry to depress you all) ... This is a bit of a long story I'm afraid but please read and help if you can
The tank is a 420L Juwel and had been running without major problems for 3 years or so. Fish stock was nothing fancy, danios, tetras, corrys, plec, gold barbs - all fairly easy to keep community stuff. A few weeks ago we ran out of water conditioner but weren't able to get our usual product (stresscoat) as we went to a different store - we were sold Interpet Freshstart instead - which as I understand it is for ponds really but we were assured it would be fine for tropical and looks like it contains the same ingredients (mainly dechlorinator). On the evening after a routine water change (incl the new conditioner) I noticed that the filter pump was not running properly, a rubber pipe had perished so it was sucking water straight in through the top of the pump rather than drawing water through the filter properly, I have no idea how long it had been like this unfortunately - I wedged it back into place as best as I could with the intention of getting a new pipe ASAP.
The next day the tank was fine, however on the morning of the day after there were scenes of devestation - pretty much all of the fish were dead or dying at the top and the water had turned milky white. Only the harlequin tetras and the catfish + 1 or 2 others survived this, but all were gasping. After some forum-checking and a visit to our local fish shop with a water sample we discovered that the nitrate level was through the roof and the milkiness appears to have been an algae-bloom. I bought a new rubber pipe to fix the filter properly and a dose of 'bactinetts' that are supposed to be live bacteria which help reduce nitrate and start up a new filter quickly in an attempt to save the remaining fish, - whether that helped or not I don't know but certainly the milkiness was clear by that evening and the fish looked happy again rather than gasping as they had been. We put this down to the filter not running properly, so we could well have had a build up of nitrates over time. Since we had everything apparently back up and running we left it a few weeks and all was well - a couple more died over the next month but that doesn't seem unexpected after such a shock to their poor systems.
Unfortunately, after another water change (25% since it had been left for a month, again with the interpet conditioner) the same pattern occured - 2 days after it went milky and the fish were gasping at the top. We hadn't restocked at this point and nothing more died, I bought another shot of bactinetts as this seemed to help previously, again it was clear by that evening.
Now we are wondering about the conditioner so last week we tried an experiment by changing the water without any conditioner at all (we don't have many fish to lose no matter what ...) it didn't bloom, no gasping. Hopefully all is well, we intend to buy some stresscoat before the next change ...
So some questions to ask... what could be the cause of the problem ? Is the conditioner we were sold to blame ? Does pond conditioner perhaps have something more in it that causes nitrate level to vary wildy in a tropical tank ? If we go back to stresscoat are we likely to have similar problems ? Or alteratively is the problem with the filter the cause of all this, and since we have it working correctly now can I restock and carry on as normal ?
Also I'd like a little advice on what to do next - we really want to put some more fish in as the 10 we have a looking a bit lonley in such a decent-sized tank. Should we monitor anything in particular for a few weeks and is there anything else we should attempt to fix before restocking ?
OK there's a lot to digest there so I'll leave it at that - any help appreciated
First off the disaster (sorry to depress you all) ... This is a bit of a long story I'm afraid but please read and help if you can
The tank is a 420L Juwel and had been running without major problems for 3 years or so. Fish stock was nothing fancy, danios, tetras, corrys, plec, gold barbs - all fairly easy to keep community stuff. A few weeks ago we ran out of water conditioner but weren't able to get our usual product (stresscoat) as we went to a different store - we were sold Interpet Freshstart instead - which as I understand it is for ponds really but we were assured it would be fine for tropical and looks like it contains the same ingredients (mainly dechlorinator). On the evening after a routine water change (incl the new conditioner) I noticed that the filter pump was not running properly, a rubber pipe had perished so it was sucking water straight in through the top of the pump rather than drawing water through the filter properly, I have no idea how long it had been like this unfortunately - I wedged it back into place as best as I could with the intention of getting a new pipe ASAP.
The next day the tank was fine, however on the morning of the day after there were scenes of devestation - pretty much all of the fish were dead or dying at the top and the water had turned milky white. Only the harlequin tetras and the catfish + 1 or 2 others survived this, but all were gasping. After some forum-checking and a visit to our local fish shop with a water sample we discovered that the nitrate level was through the roof and the milkiness appears to have been an algae-bloom. I bought a new rubber pipe to fix the filter properly and a dose of 'bactinetts' that are supposed to be live bacteria which help reduce nitrate and start up a new filter quickly in an attempt to save the remaining fish, - whether that helped or not I don't know but certainly the milkiness was clear by that evening and the fish looked happy again rather than gasping as they had been. We put this down to the filter not running properly, so we could well have had a build up of nitrates over time. Since we had everything apparently back up and running we left it a few weeks and all was well - a couple more died over the next month but that doesn't seem unexpected after such a shock to their poor systems.
Unfortunately, after another water change (25% since it had been left for a month, again with the interpet conditioner) the same pattern occured - 2 days after it went milky and the fish were gasping at the top. We hadn't restocked at this point and nothing more died, I bought another shot of bactinetts as this seemed to help previously, again it was clear by that evening.
Now we are wondering about the conditioner so last week we tried an experiment by changing the water without any conditioner at all (we don't have many fish to lose no matter what ...) it didn't bloom, no gasping. Hopefully all is well, we intend to buy some stresscoat before the next change ...
So some questions to ask... what could be the cause of the problem ? Is the conditioner we were sold to blame ? Does pond conditioner perhaps have something more in it that causes nitrate level to vary wildy in a tropical tank ? If we go back to stresscoat are we likely to have similar problems ? Or alteratively is the problem with the filter the cause of all this, and since we have it working correctly now can I restock and carry on as normal ?
Also I'd like a little advice on what to do next - we really want to put some more fish in as the 10 we have a looking a bit lonley in such a decent-sized tank. Should we monitor anything in particular for a few weeks and is there anything else we should attempt to fix before restocking ?
OK there's a lot to digest there so I'll leave it at that - any help appreciated
yeah i know how you feel i lost 12 fish within a 2 week period, very disheartening.
