PlanetCatfish.com

90gal
no heater, temp 68-76 depending on season
any suggestions?

I can't suggest any pleco for a coldwater tank, being as they are from tropical South america, although there may be a specie or two that could work. Rather, I would recommend a large school of Corydoras paleatus, aeneus, or panda . You could easily fit 24 (or more) peppered corys in a 90 gallon with some goldfish.
If some sort of side sucker is what you want, then try borneo suckers (aka. butterfly plecos, coldwater plecos, etc.), but they do not eat algae. They are a type of loach and are an interesting addition to any coolwater tank.
Hope I've been helpful.
Josh

If you do have a heater, and set it for perhaps 20'C (68'F), you could keep .

They go fairly well together with goldfish, and will certainly eat algae well.

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Mats

I would recommend a large school of Corydoras paleatus, aeneus, or panda .

I would personally advise against Corydoras, as a goldfish tank will certainly be more polluted than you would want with these more sensitive catfish.

How about a good old common pleco () ?

They are well able to tolerate the cooler water and higher levels of pollution.

I've tried P. pardalis in a tank without a heater (probably at 65-68F) and it died within a day. The reason I recomended Corydoras was because they can take the cooler temps well.

How about rubbernose plecos?

require fast moving water, which isn't what most goldfish like.

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Mats

I've tried P. pardalis in a tank without a heater (probably at 65-68F) and it died within a day

I wouldn't expect that. I've kept them in unheated goldfish tanks and outside in UK summers (certainly not renowned for being tropical).

If memory serves me correctly, he even sucessfully overwintered in the garden one year!

Hypostomus Commersoni
Ancistrus Cirrosus
There is also a fish exported from Argentina WATA WATA pleco
There are also several Cochliodon from cool water
Snow king Pleco..?

MatsP wrote:

Chaetostoma

require fast moving water, which isn't what most goldfish like.

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Mats

I've got alot of fast moving water. They're commons.

sojapat wrote:Hypostomus Commersoni
Ancistrus Cirrosus
There is also a fish exported from Argentina WATA WATA pl*co
There are also several Cochliodon from cool water
Snow king pl*co..?

Neil, could you produce a photo of A. cirrosus? If you can, we could add it to the list of Ancistrus species in the Cat-eLog.

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Mats

LittlePuff wrote: I've got alot of fast moving water. They're commons.

What sort of flow-rate do you consider fast here? I'm thinking 12-15x turnover rate, which means about 1000 gph or more in your size tank. At the very least, you need 500 gph turnover. For those preferring metric numbers, that's between 2000 liter per hour to over 4000 liter per hour, on a 350 liter tank.

You could perhaps get away with a bit less if you create a corner which has a particularly high rate of turnover.

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Mats