The thing about water

My enthusiasm for twice daily water testing evaporated very quickly, especially when the number of fish tanks in my home increased. Water testing became a once a week thing for a while, then once a fortnight, then employed only when fish either didn’t look healthy or were found dead.

My fish looked energetic, had no marks on their bodies, ate well and not too often, and in three of my tanks the fish were continually breeding, or attempting to breed. I figured I must be doing something right and stopped stressing about the water quality. I had plenty of other things going on in my life that were stressing me out and I felt relief at being able to scale back a bit on aquarium maintenance.

For most fish, the slightest trace of ammonia can be deadly and the goal is to have zero trace of it in the tank. The ammonia test kit that I use displays the water reading by change of colour, from bright yellow for no traces of ammonia and a dark green reading for high concentration of ammonia.

The difference in colour between having a zero reading (bright yellow) and a reading of 0.25 parts per million (ppm) is slight (yellow with a greenish tinge) and readings of under 0.25 ppm are very hard to detect. The best rule of thumb to use is the lower end of the spectrum – if the water isn’t bright yellow and looks pale yellow it is safer to assume there is ammonia in the water and do a 30% water change*.

I had found that out the hard way once before, by putting fish in another tank that had a slight trace of ammonia and losing most of them. One of the problems is that API’s freshwater ammonia color card does not display the “pale yellow” in-between reading, meaning that, like a lot of other amateur aquarists, I have made the mistake of believing that test colour of any shade of yellow means everything is hunky-dory.

It has been a sad week at TankTales HQ. Five fish from one tank succumbed to a slight increase in ammonia – at least I think that’s what it was. The PH was all over the shop as well, but the ammonia increase is the most likely culprit.

The tank most recently housed a breeding pair of angelfish, two bloodfin tetras, two golden widows, and a red rainbow fish from Papua New Guinea. Now, just the two angelfish remain.

Koi angelfish and bloodfin tetra

On Thursday I noticed the bloodfin tetras were missing. I assumed that after a month of seemingly getting along well, the angelfish had preyed on the tetras. The most likely scenario was that the angelfish had resumed their breeding activity and had become aggressive to protect their eggs. I couldn’t see any eggs or fry, but knew from past experience with this pair that they were good at hiding their offspring and were very protective of them; right up until the moment that they ate them, as they had done at least six times in the previous six months. I went to work, feeling sad about losing the tetras and feeling guilty about failing to protect them.

Black ghost angelfish and two golden widows.

On Friday night, I couldn’t find the red rainbow fish, but the other fish looked okay. I tested the water for ammonia and to my eye the colour changed to bright yellow. I figured I had an aggression problem on my hands, and thought about which of my other tanks I could transfer the widows to, so they would be out of harm’s way. I couldn’t really transfer them to any of the other community tanks without putting them at risk from the current inhabitants, so I decided I would return them to Rayonne Aquarium in the morning and ask that they be re-homed.

Rainbow fish, golden widow and the tail of the black ghost angelfish

On Saturday morning the rainbow fish appeared again, but I could only find one widow and it was swimming vertically. That’s not a good sign. I located my floating fry cage and gently lowered it into the “miracle” tank in the kitchen – so named because every sick fish I have put in there has recovered. It currently houses ten mollies, five platys, six bettas, two clown loaches and a bristlenose pleco – they are all well, healthy and getting along, and the water readings are always perfect.

I scooped the widow out of the water and transferred it to the fry cage, where it lay on its side with twitching fins. It didn’t last very long. For the first time the “miracle” tank did not live up to its name.

Back at the anglefish tank, I grabbed a bucket and the vacuum water siphon and got the water change started with a big suck on the end of the siphon pipe. As the bucket filled and nasty goop was sucked out of the gravel I moved the rocks, driftwood and other accessories.  Under an aquarium tunnel that looked like a hollowed out tree trunk that had been cut in half lengthwise, I found the second golden widow, already dead. Poor thing. I scooped it out and added it to the compost bin – the eventual final resting place for all of my fish.

I did a 40% water change while vacuuming all of the gravel and with a net I fished out large particles of rotting leaves and stems from the aquarium plant cuttings I keep in most of my tanks. The angelfish like the bamboo leaves for spawning and the other fish welcomed the hiding places provided by strings of baby’s tears and ludwigia. I change the plants every one to two weeks and I take out the stems that are left once the fish have fed on the plant leaves. Despite that regular clean up, there was still a lot of leaf and stem litter covering the gravel.

A test of the water gave me a pale yellow ammonia reading, so I did another, smaller water change (about 20%) and hoped for the best. Two hours later the red rainbow fish, which had been swimming around quite happily, was found dead on the gravel bed.

I tested the water again this morning and got the same pale yellow reading so I did another 30% water change, a few hours ago. This time, the ammonia test result is bright yellow and I am less fearful about losing my beautiful angels. The PH is back within the preferred range too.

All of the other tanks have been tested too. There's no ammonia present, but some of the PH readings are not good so I’m doing lots of water changes today.

I’m keeping my fingers crossed that the angels make it. If they’re still alive tomorrow I will give them a small amount of food (they haven’t been fed since Thursday) and keep hoping for the best.

Wish me luck.

#tanktales

*This is my personal opinion and is not professional advice.