Bristlenose catfish ageing

[Spiriko]

Hi I've owned fish for the last 13 years so I'm not new to the hobby but I recently got two bristlenose catfish or pleco and I have never owned them before they are about an inch and a half long one is an albino female and the other a male normal with some lip whiskers I've had them for almost four months and was wondering if anyone could give me some tips or tell me how old they are.

In case you want to know I keep them in a 40g tank with caves plants fine gravel substrate (I know some people don't like it cause it can damage bristles but I've never had that problem) some corydoras, young plates, and neon tetras, I have good filtering heaters and an airstone plus I do regular 20% water changes.

 

[Fallen_Leaves16]

Do you have any pics? Ancistrus cf. cirrhosus usually attain 1.5 inches within ~6-10 months, depending on the diet and water parameters.

 

[Spiriko]

They are hard to get photos of but I was lucky and the male was out on the glass this morning I even got to measure him fir the first time in a little bit and he is almost at 2 inches (he has whiskers they are just hard to see at this angle) the female is the same size as him.
I feed them a mix of fish flakes, alge wafers, cucumber, and frozen foods and the water parameters are kept relatively nicely with PH being always between 6.5 to 7.5 ammonia and nitrite did have a small spike about a month ago but it was sorted quickly and the tank is kept at a stable 23 °C.

 

[Fallen_Leaves16]

Looks like ~9 months of age, possibly younger or older (may vary based on several factors). Either way, you have a fine, healthy pleco that has a long life ahead of them.