I have a 135 planted tank that had been neglected over the summer after I had lost the few neons in it from an accidental overfeeding. The tank had become badly overgrown with algae and some of the plants had been lost.
The tank runs a large Fluval outside filter, two sponge filters, has CO2 diffusor and 6500K four lamp illumination. The tank is largely open to the air at the top, for air exchange.
After removing the plants, the loose algae and doing a syphon cleaning of the gravel, about 80% of the water was replaced the plants were replanted and more were added. The water was allowed to clear up and three Siamese Algae Eaters were added. They seemed fine for the first day but became listless and then died by the third day. Testing showed no ammonia or nitrites, however the pH of the replacement water was quite high about 8.5, so I syphoned off 1/2 the water and replaced with rainwater. Since I was unsure of the tank's safety I purchased 10 feeder swordtails and added them to the tank. pH was near 7.2 after the water change, but the next day all the swordtails had also died. I replaced 1/2 the tank's water with R/O - D/I water (0.0 ppm) and then added 3 more SAE, this time they seemed Ok for two days but then once again died. The only animal life not affected seems to be the few snails in the aquarium. I did one more water change today R/O - D/I 25% of the volume and tonight added one Black Skirt Tetra.
I have had no problems in the past with this tank, with the same basic setup that I have now. Other tanks in the same room are fine and the fish appear healthy. I don't believe it is "new tank syndrome" because the tank had been set up for several years and only the detritus and old water was removed, there should be adequate bacteria in the gravel bed for so few fish in a 135. The plants are unaffected, there is some brown hair algae growth which it gradually giving way as the plants take over. Could this be the result of some poisoning of the aquarium, perhaps an insecticide?
The tank runs a large Fluval outside filter, two sponge filters, has CO2 diffusor and 6500K four lamp illumination. The tank is largely open to the air at the top, for air exchange.
After removing the plants, the loose algae and doing a syphon cleaning of the gravel, about 80% of the water was replaced the plants were replanted and more were added. The water was allowed to clear up and three Siamese Algae Eaters were added. They seemed fine for the first day but became listless and then died by the third day. Testing showed no ammonia or nitrites, however the pH of the replacement water was quite high about 8.5, so I syphoned off 1/2 the water and replaced with rainwater. Since I was unsure of the tank's safety I purchased 10 feeder swordtails and added them to the tank. pH was near 7.2 after the water change, but the next day all the swordtails had also died. I replaced 1/2 the tank's water with R/O - D/I water (0.0 ppm) and then added 3 more SAE, this time they seemed Ok for two days but then once again died. The only animal life not affected seems to be the few snails in the aquarium. I did one more water change today R/O - D/I 25% of the volume and tonight added one Black Skirt Tetra.
I have had no problems in the past with this tank, with the same basic setup that I have now. Other tanks in the same room are fine and the fish appear healthy. I don't believe it is "new tank syndrome" because the tank had been set up for several years and only the detritus and old water was removed, there should be adequate bacteria in the gravel bed for so few fish in a 135. The plants are unaffected, there is some brown hair algae growth which it gradually giving way as the plants take over. Could this be the result of some poisoning of the aquarium, perhaps an insecticide?
