Frogs in pond filter box - How?

[werdnal]

MIL has an ornamental garden pond with goldfish and a pump/filter unit. The filter is fully enclosed in a plastic box, with a wooden slatted lid. The slats on the lid are less than half an inch apart, and to disguise the lid and keep it secure, she puts a heavy potted plant on top.

Yesterday, we serviced her pump, and whilst there she took the lid off the filter box and exclaimed "Look they are back again!". Inside the filter box were 2 very healthy large frogs - must have been over half the size of my fist, along with a tiny toad. The toad I understand, as it would fit between the slats, but how are the frogs getting in there? She says she takes them out every 3-4 weeks when she cleans the filter mat, but they are always back the next time.

We are a bit concerned as she wants to switch on her UV lamp in the filter again now the water is warming up and going green, and we don't want to burn them or give them a tan!

How are they getting in there?

[~T~]

It's possible they could squeeze through the slats as frog bodies are pretty squishy. You don't say what the filter outlet is like, they may have climbed in that way.

[werdnal]

We thought they might be getting in the outlet, even though it is a vertical drop about 8 inches into the water, so put a small piece of mesh over the end a few months ago, but they are still getting in.

Its hard to see how such large frogs would be able to squeeze through between the slats, but that seems to be the only way in!

[tom00_uk]

they can squish through tight spaces, try the mesh over the slates and then see if they come back

[dampflippers]

The problem is in the sucking end of the pump, where the water is sucked from the pond. Either the end of the hose, or the whole pump if immersed needs better filter on it. Try a pair of tights.
They will have been sucked through the mesh when just hatched (ie only 1 cm long) and have been surviving on algae etc in the filter box.

I'm afraid that this is quite a common occurrence that ponds with a pump don't have good populations of amphibians, especially newts becuse the babies either get minced by the pump or sucked up or get squashed in the pump's perforated plastic casing.

You can now put the tads back in the pond, but please try to make the pump safer.

[werdnal]

Originally Posted by dampflippers

The problem is in the sucking end of the pump, where the water is sucked from the pond. Either the end of the hose, or the whole pump if immersed needs better filter on it. Try a pair of tights.
They will have been sucked through the mesh when just hatched (ie only 1 cm long) and have been surviving on algae etc in the filter box.

I'm afraid that this is quite a common occurrence that ponds with a pump don't have good populations of amphibians, especially newts becuse the babies either get minced by the pump or sucked up or get squashed in the pump's perforated plastic casing.

You can now put the tads back in the pond, but please try to make the pump safer.

No - the pump already has a fine mesh on it, which means the tads won't get sucked in. These frogs are very large and MIL checks the filter box every few weeks and removes them. Then they are back again the next time she checks it. They are far too large to be this year or even last year's tads, that have been sucked up, trapped inside and just grown there.

I think they are definately getting in through the slatted top. We are going to make a better lid, without the gaps, and this should hopefully stop them!