Need advice on molly fry care. urgently!

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If your tap water has Chlorine in it, then every time you clean your filters you are killing the bacterial colony and starting your cycle over again, at least partially. You really need to read up on the Nitrogen cycle. It is the most basic thing that all aquarists need to fully comprehend.

You must never, ever rinse your filter media under tap water, especially if it is the only media in your filter. The U2-U4 filters have a separate compartment that houses bio-media balls that you would only lightly rinse in a bucket of water you pulled from your tank during a water change, and then only to loosen debris.

With a floss-only filter, such as the one you have, you should clean it periodically as recommended by the manufacturer, or more or less often depending on your tank load. But you should only take water pulled from the tank or tap water that has been sufficiently de-chlorinated and rinse it in that, squeezing, etc.

I think the manufacturer recommends that you replace one pad every few months, leaving the other pad to 'seed' the new pad with a bio community.

Constantly over cleaning your pads will stress your fish out and lead to disease. It is possible that this isn't happening because the rest of the filter that sits in the tank still has some biological colony residing on it, and this may be your saving grace. That or it you don't clean it too much under tap water, you'll still have surviving bacteria.
i clean it v rarely.... i no thats bad but i knew there was a build up of good bacteria.
i WANTED to clean the fry filter every week now, but i may add some the established filter pads and let the good bacteria grow.

btw she had 30 or more babies, all just less than an cm long, no stillbirths (havent checked the plant) and 4 eggs (yummy snaks for mummy)!!
here r some pics, they look like their happy :D


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I have 6 female and 2 male silver mollies and 3 black mollies 1 male 2 female, 13 babies right now , 1 of babies got big then died,never had more than 5 babies from 1 batch of fry, mine are doing well , do not use salt with mollies unless treating for disease,mine eat brine shrimp,bloodworms and much more.
ty, well day1 is nearly over and the chemistry is

ammonia- 0-0.25ppm (more 0ppm)
nitrite- 0ppm
nitrate- 5-10ppm

all babies looking healthy, fit and hungary!
fry don't produce very much ammonia, but you still need to watch the level and do PWCs to make sure it stays low. Test for Nitrites as well. Nitrates you don't generally have to test if you're doing 50% daily water changes, which you should be doing in an uncycled fry tank. Do the tests before the PWC (at least that's what I do). Keep an eye on pH also and if your tap water is very different, pull the water from the 20g for a week or two, once the fry are that old, IMO it's safe to do tap water changes.

Congrats on the good batch of fry! If they made it through the first day, you're pretty safe.
good for u!

im not changin water 2day as they arent even day old but defo in morn and will probs use half main tank water and half treated tap water.

good luck with the fry, keep me updated
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