I used to use rabbit poop to fertilize my planted fish tanks. a few for each tanks every few weeks. I never had any problems from it.

I also used it to grow greenwater to raise daphnia to feed the fish. I have since moved and no longer have the fish and my bunny poop connection is also gone now but I would still use it if I had it.

It should be fine to use but I'm sure it will be missing something the plants would need. Make a worm composter and compost them first if you're concerned about using it fresh.

SSG,

In an old Cactus and Succulent Society of America journal, there was a recipe for horse poop tea for one's plants.

Just in case there might be too much nitrogen, as is often the case, I'd let it decompose for a month or so, but perhaps you're using it in such small concentrations that it doesn't matter.

Still, the world is full of undiscovered inventions/ideas, and you could be sitting on the golden dunghill.

Guinea pig and rabbit pellets can be used straight from the animal without burning plants, unlike horse or cattle. I'd say go ahead. I'd be more concerned by the left over bedding than the droppings themselves. If you're going to use bedding also, switch to paper bedding or corn cob bedding. I use the pellets in my soil mix sometimes if I have some extra available. 5 pellets in a gallon of water would be awefully weak, though.

First, I'll admit that if you could get it to work out for you, that there would be a certain sense of satisfaction in knowing you did it. For myself, I don't think the risk:reward ratio warrants the use of a poo solution. I'm going to feel like a salmon swimming upstream here, but here's why I wouldn't use it:
1) You have no idea what you're supplying to your plants. How much of what nutrients. NPK, Ca, Mg, S, Fe ......?
2) The odds are very high that, because you have no idea of what a proper dosage might be, you'll either be applying too much or too little. Since your post infers you'll be careful, let's assume you'll be applying too little.
3) Because you'll be trying to remain on the safe side and will apply too little, nutritional deficiencies will develop. Any deficiency stalls growth, but it's unlikely you'll know which nutrient(s) is/are deficient, so you'll need to apply fertilizer anyway, if you wish to correct.
4) It's unlikely that the poo will contain a proper balance of nutrients, that certain nutrients will be well represented and some will be absent, or nearly so. If you then add a properly balanced fertilizer that is necessary, the additional nutrients in the soil from the poo are superfluous and only contribute unnecessarily to the level of total dissolved solids in the soil, which makes it more difficult for the plant to take up water and nutrients.
5) You're much better off to use a fertilizer that you can control the dosage of and that you KNOW has the right balance of nutrients, than you are to try to play a guessing game with a fertilizer that is high in some nutrients and low in or lacking others, and then try to correct the imbalance with a balanced fertilizer.
6) Organic forms of fertilizers (like poo and fish emulsions) rely on micro-organism populations in the soil to break down organic molecules into an elemental form that plants can use. These micro-organisms experience boom/bust cycles in container culture and cannot be relied upon to deliver the nutrients just because they are present in soils. If they are locked in organic hydrocarbon chains, they are unavailable until those chains are cleaved by soil organisms.
7) Organic fertilizers used on container media tend to form hydrophobic algal caps on exposed soil surfaces and encourage the proliferation of fungus gnats.

FWIW, none of the above are associated with the use of soluble fertilizers like MG or Foliage-Pro.

Al