Still born fry!

[storm67]

Hi all

Just after some advice re my blue snakeskin pair. They have been spawning for quiet a while now without much success. Now they are getting wrigglers that they move on the cone as soon as they hatch. It seems however that they arent wrigggling and seem to stop growing after they hatch.

Any ideas for this would be very welcome.


Larry

[mmorris]

Hi all

Just after some advice re my blue snakeskin pair. They have been spawning for quiet a while now without much success. Now they are getting wrigglers that they move on the cone as soon as they hatch. It seems however that they arent wrigggling and seem to stop growing after they hatch.

Any ideas for this would be very welcome.


Larry

More info might be useful. What are your water stats? Water change regime (how much and how often)? Does the wc water have exactly the same perimeters? How long after hatching are they dieing? Do they fall to the floor first? How many batches have died?

[storm67]

I knew you would ask that lol. Just finished testing.

Tank stats: 3 ft bare bottom 160 litres. canister filter with sponge on intake and tapped to low flow while eggs hatching.

Water: Rain water: Nitrate 5, Ammonia 0. Nitrite 0, pH 5.5, GH 40ppm, KH 0, Phosphate .1ppm.

PWC: 40% every few days but once eggs are laid only daily 10% to remove waste etc.

Ive had the pair for 9 months at which time they spawned and raised about 50 fry to 15mm size that then died off one by one. Since then they have spawned regularly (every week) eggs go from being eaten within a cpl of days to hatching and being moved but showing no signs of life. They do seem to be looking after them and very protective of their eggs. I have recently gone back to rain water as i seem to get to hatching stage at least as compared to tap water. Not sure if they are hitting the bottom of the tank first but will watch. If they do they are being placed back on the cone by the parents.

Larry

[storm67]

Sorry more info

Usualy only get a small amount hatch and then die off. Once I give up and turn the night light off they are eaten. This batch is bigger however as i seem to get better hatch rate on the rainwater even tho my tap water isnt hard at all (70ppm). The last four or five batches has been like this with the hatch rate getting higher but still no movement after being moved on the cone.

[mmorris]

I wonder if it's your rainwater. I certainly wouldn't use mine! I hate to think what the rain washes out. It may be that you got to hatching stage when you started using rain water simply because the fish had matured to the point where the eggs are fertilized. If so, hatching wouldn't have anything to do with the rain water.
Newly hatched fry cannot cope with even minor changes to the ph and temp of the water. Were you pre-heating the rain water? The temperature needs to be exactly the same when you do a wc. Since the rain water had no kh and the ph was low, I suspect you were experiencing a ph drop, particularly when you reduced the wc's to 10%. I recommend you check the ph and kh out of the tap, age the tap water 24 hours in an aerated bucket, and test it from the bucket. Also, measure it from the tank. Are they at all different? If there is a difference, you need to age your tap water 24 hours or so. How often do you wipe down the tank? I would keep the tank really clean, watch the ph and forget the rain water. I change 1/3 to 1/2 every other day or third day until I start bbs and then it's daily.

[storm67]

yes I do get pH drops due to the low Kh and wondered if this was the problem. I wipe the tank out very regularly and keep it really clean also run UV. My tapwater ph is 7 out of the tap but climbs to 8 after a few hours then seems to settle around 7.5. Ive tried dropping this with acid but still get the unstable ph. have added coral to the filter but def get lower hatch rate. The fish produce a batch of fry when i first got them so they are mature enough. At the time i was using non aged tapwater and treating with prime before adding to tank.