Malta Aquarist Society

  Hi

 Does anybody know how to cut the bottom of a bottle, without breaking it to pieces. I remember once at school we had been  told how to do it at a science class, But it was ages ago. I think it had to do with warm and cold liquid or something, and the glass is cut perfectly.; I need it to make a brine shrimp hatchery as the bottles i am using some of the eggs remain at the bottom and do not hatch.

Any advice greatly appreciated

 Frank

Hi Frank,

I gave you an advise how to cut a glass bottle and offered to cut it for you on the Killifish for Everyone link.

There might be other reasons why not all the brineshrimp eggs are hatching. Water circulation, in your case, is one of them. Another reason could be the eggs quality, where have they been stored and how long have the vacuum can had been opened. Water temp. is also another factor. The ideal temp. is between 26 to 28C. Now with the very hot temp. 35C. we are having, most of the nauplii die just after hatching, causing the whole lot in the hatchery to go off, so more frequent sea water changes are required.

Never be tempted to buy cheap eggs. The international market for good products is high and cheap purchases will result in poor hatchings. ( L-irhis, gholi jghid il-Malti )

Charles.

 Hi charles

Thanks for your advice. I was wondering should i use sea water instead of making it myself. I think the stock i have is old, as i have had them in the fridge for many years. They still hatch but the rate of hatching is small. When you say more sea water change do you mean you do not use the same water again to hatch the brine shrimps?

 Frank

Hi Frank,

If the brineshrimp eggs that you have had been from a good quality, even though they had been in the fridge for a number of years, they should give good results had they been stored correctly. But most commercial suppliers suggest that once the vacuum can had been opened, the eggs  in it are to be consumed within 3 months.

When the air temp. in my fishroom is between 24 to 28C. I keep using the same sea water for up to a month. But when the weather is as warm as it is these days, above 30-35C. I change my seawater every 15 days. Some of the hatched nauplii are weak and die just after hatching or even before and they pollute the hatchery. I collect my water just infront of your home, at the tip of the pier. I always wait for the wind to be blowing from the North and collect the water at about 7.00 am before most people are off to the sea. In doing so, the water is not polluted too much.

Charles.

 Yes you have an advantage as you both leave minutes away from the sea. I have noticed that when I use " fresh " sea water, the hatching rate is far more better then old sea water . Surely for you Cikkus, getting some fresh sea water is not that difficult, now that I know where you live !!!!. You can always confirm that your brine shrimp eggs have gone bad if you get hold of another batch of brine shrimps from someone else and you get a far more better rate of hatching. 

martin