Assuming I get some GW pretty soon (or infusoria of some sort). How much should I dose to a 25 gallon - and how often. Couple times a week or daily? About a pint of the GW or a bit less (or more)? Thanks. bob
The main idea for this GW is to get the infusoria or rotifers for the meat food source and also to have some greens with it, as the rainbows are omnivorous leaning towards little creepy/crawly things to eat.
I have used the airline tube method with MANY little ones in the past and it varies according to how many young and their "eagerness" to eat. Like with baby brine shrimp feeding just watch the bellies of the young and see that they are full and well rounded after the feeding time. or another approach is to set the jar say a gallon pickle size, on top of the tank and put another one in the window to ferment while the first one is dripping, that way you can have the food source constantly available.
With the drip line you can tie a loose knot in the airline about halfway down to the tank and tighten this little knot enough to allow a consistant drip of about 10-20 drips per minute. This same idea can be conformed to drip method of aclimating new fish to a tank from extremely different water types (like from across the country).
You'll know the jar has infusoria when it becomes a little cloudy when looking through it towards the light of the window(or bulb). If you happen to have a small lake, pond, or stream around go collect a few rotifers (infusoria) by collecting some of the water in a bucket and using it for the starter culture. All local bodies of water have some form of rotifers in it and you'll see them under a microscope or sometimes just with plain eyesight.
Adding food to the jar in the light source with say liquid fry food will keep the culture gowing for around 3-4 days to a week, then, the whole thing should be dumped out and a new jar started, as the old setup has more bacteria than infusoria in it which is bad for the young.
The feeding of this type of food will need to be consistantly fed for about 3-4weeks for this type of young rainbows as they grow VERY slowly like I said. Most young fry of say cichlids or larger fish will only need this feeding, if at all, for about 3-4 days so you can see what your up against with rainbows. They can then consume baby brine shrimp, or crumbled flake, frozen daphnia and so on.
You can acquire gallon size pickle jars from local restaurants by asking the people that cook there if they have a couple, or just buy some of those little meat weenies "Hot" type or not and remove the food stuffs, then clean the jars VERY well with a little bleach and hot water from tap for a few hours. be sure the jars are squeeky clean to the touch.
The link below is for the best book I have found on live foods culturing and such things in case anyone reading wants the full blown deal of this topic.
Thanks for asking and please don't hesitate to ask if something does not make sense in the above writing.