Ants!

[Jeremy180]

Terro liquid ant bait's active ingredient is Borax.
considering some of your previous posts, I would read this article before using it if I were you....
http/pestcemetery.com/borax-beauty-and-the-beast/
Edit: A more in-depth article.
http/www.fs.fed.us/foresthealth/pesticide/pdfs/022406_borax.pdf
 
There is one good bit of news, quoted from the second link:
"In fish and aquatic invertebrates, acute exposure to borax and boric acid appears to have a 50 relatively low order of toxicity. In fish, 96-hour LC values range from >100 mg B/L in 50 razorback suckers and squawfish to >1100 mg B/L in bluegill sunfish. The 48-hour LC values for Daphnia magna range from 126 to 141 mg B/L. Limited information is available on chronic exposure of fish to boric acid and borax. Chronic reproduction studies in daphnids yield an NOAEC for reproductive effects of 6 mg B/L."

 

[Chad]

Remember that the only way to get rid of a colony is to kill the queen. You can't do that with methods that only remove the ants that you see. If they are attracted to the water source, or food dropped on the floor etc. they will keep coming until the queen is good and done for. 

 

[eaglesaquarium]

Remember that the only way to get rid of a colony is to kill the queen. You can't do that with methods that only remove the ants that you see. If they are attracted to the water source, or food dropped on the floor etc. they will keep coming until the queen is good and done for. 

 
 
This is true...  dealing with the scouts or the foragers just deals with the symptom.  The queen is at the heart of the issue.  IF you can find the hill and place the diatomaceous earth around it (remember to do it when there is very little moisture around), this can actually starve out the queen as she'd be unable to get any food from any of the scouts/foragers... but that would take a while.  The good news is that its an 'all-natural' solution and it is 100% safe around pets and children. 

 

[Baccus]

The ants that are on the tank/ filter will die soon enough if cut off from thier home base colony. From memory ants only have roughly a 24hr window before they need to be back in the nest and feed. Some ant species even change their nest chemical smell daily and any ants that didnt make it home the previous day and try to enter the nest with the old chemical smell will be killed as strangers.
The reason I point this out is I have found an excellent deterant of ants to be critic acid melted in water to make a runny paste, paint this mixture at the places the ants are using to enter thr house and the ants wont cross it. It is not a "forever" solution and will need new applications as the mixture dries up and disintergrates. If you didn't want to try commercially produced critic acid you could try using the rind of a citrus fruit such as grapefruit, orange, mandarine. Or you could even just use the straight juice of a lemon or lime and paint or spray the areas the ants are entering.
 
Another option which again does not kill the ants is to coat legs of stands that the ants are climbing up with vasaline although personally I have found Vicks (the crest rub you use when you have a cold) worked an absolute treat. Oil in your case some type of cooking oil can also work but I find it tends to get tacky and have everything stick to it and is nigh on impossible to get back off what its been put on.
 
Other deterant options for keeping the ants out of the house include ground up cinnamon, and even peppermint oil.
 
Who knows you may even want to make your own mix of cinnamon, peppermint oil and lemon juice and see how the ants deal with that combination.
 
Oh and ants falling in the water I would worry about too much unless they are a particular species that is well known for having a wicked bite. Ants and ant eggs have been a fish food for a very long time.

 

[RainboWBacoN420]

Well, last night they took the poison. They're still working back and forth, so I assume the queen is still kicking.
Ants have returned to the filter. I clean hundreds of them off with duct tape aerial attacks last night.
The ants taking the poison are near the vent, away from the aquariums. I found more ants on the filter of the 55 now. Looks like I'll be busy again tonight. I think the fish have already started picking off the floaters, hopefully that won't cause issues later down the road. I would expect it to be normal to feed off of ants, in the wild... But it he aquarium where it's just filtered water. I don't know, I wouldn't expect problems to arise, but just thinking of what would go wrong here.

 

[Jeremy180]

Well, last night they took the poison. They're still working back and forth, so I assume the queen is still kicking.
Ants have returned to the filter. I clean hundreds of them off with duct tape aerial attacks last night.
The ants taking the poison are near the vent, away from the aquariums. I found more ants on the filter of the 55 now. Looks like I'll be busy again tonight. I think the fish have already started picking off the floaters, hopefully that won't cause issues later down the road. I would expect it to be normal to feed off of ants, in the wild... But it he aquarium where it's just filtered water. I don't know, I wouldn't expect problems to arise, but just thinking of what would go wrong here.

I've seen reports of studies where the gut contents of several wild-caught tropical fish were over 50% ants by weight, So the main thing I would be worried about, if anything,  is what sort of contaminants the ants may be introducing to the aquarium, although given their (the ants) size, the quantity should be pretty low.

 

[RainboWBacoN420]

 

Well, last night they took the poison. They're still working back and forth, so I assume the queen is still kicking.
Ants have returned to the filter. I clean hundreds of them off with duct tape aerial attacks last night.
The ants taking the poison are near the vent, away from the aquariums. I found more ants on the filter of the 55 now. Looks like I'll be busy again tonight. I think the fish have already started picking off the floaters, hopefully that won't cause issues later down the road. I would expect it to be normal to feed off of ants, in the wild... But it he aquarium where it's just filtered water. I don't know, I wouldn't expect problems to arise, but just thinking of what would go wrong here.

I've seen reports of studies where the gut contents of several wild-caught tropical fish were over 50% ants by weight, So the main thing I would be worried about, if anything,  is what sort of contaminants the ants may be introducing to the aquarium, although given their (the ants) size, the quantity should be pretty low.
 

That's exactly the whole point of why I don't want these ants near my aquariums.