Grazer stocking density?

[fermentedhiker]

Playing around with stocking lists for an upcoming build and I have a question about grazer compatibility. Is there a ball park figure(I know there are other factors to consider such as size/aggression etc...but lets keep it to this parameter for this post) for how many pounds of live rock, or tank gallons per grazer(blennies, tangs, dwarf angelfish etc...) For example would a starry blenny, a tomini tang, and Cherub angel work in a 90 gallon with 100-130 lbs of live rock?

Thanks

 

[dppitone]

I know of no functional relationship between live rock and the type of fish you'd like to add. You'll probably need about 50 pounds of rock to set the filtration for three fish, especially if you used live sand. Any rock after that would be for other purposes/preference.

 

[ca1ore]

Yeah, too many variables to be able to come up with any useful rules-of-thumb. Different tanks grow algae at different rates based on import and export of nutrients. Algae is consumed by a broad range of animals beyond just the fish. My approach has been to manage export aggressively, employ a sizable CUC, and keep one Tang per 50 gallons. If I see algae growth in the display I add more CUC. If I see no algae, I supplement feeding with nori more frequently.

 

[fermentedhiker]

Thanks for the replies, but I'm thinking more from a conflict over perceived resources than thinking of them as cleaners. I've been following snorvich's thread on compatibility and on several occasions he recommended against what the poster wished to add because they already had a grazer and so shouldn't add another.

At first I was thinking that it would be based on tank size, but it struck me that grazers browse the rock structure and so lbs of live rock in the dt would be more relevant. I realize that live rock amounts are often based on tank size, but these days that can vary a lot from one hobbyist to another(even by as much as 100% when you compare a spartan aquascape to 2lbs/gallon system).

The other way I thought of looking at it was for the sake of simplicity using the minimum tank size recommended for that species. For simplicity sake I'll stick to LA. They list a Starry blenny minimum as 30gallons, a Cherub angel as 55, and a tomini as 75. Using these as additive minimums to keep the blenny and angel would require 85 gallons and to add the tang would mean a 160 gallon tank. This method starts to look excessive, but conservative approaches are inherently safer.

Thoughts?

 

[dppitone]

The algae that grows in your tank is not a "resource" to the tangs in that sense of the term. It's incidental that they eat it, if you have the right type. So there is no competition in that context so you can put that one away.

Also, the "minimum" tank recommendation don't accumulate in the way you're suggesting. That's not how that rating is meant to work. Your stocking is fine for the tank under normal circumstances.

 

[fermentedhiker]

The algae that grows in your tank is not a "resource" to the tangs in that sense of the term. It's incidental that they eat it, if you have the right type. So there is no competition in that context so you can put that one away.

Also, the "minimum" tank recommendation don't accumulate in the way you're suggesting. That's not how that rating is meant to work. Your stocking is fine for the tank under normal circumstances.

You may be right with regard to Tangs since they don't hold territories, but other grazers perceive them as competition for sure and will try to defend their "patch" against the tang.

I realize that minimum tank sizes are not additive normally. You're missing the point of that proposal. For instance I could easily have additional fish in a 30 gallon with a starry blenny, but possibly not another grazer. Additions would have to be fish that occupied a different ecological niche. The same problem arises with multiple pod consumers in the same tank. Although for mandarins this can be a literal competition for resources(if they won't take prepared foods) instead of just an instinctive "perceived" one.

 

[dppitone]

Ok just trying to help with your question.

 

[Dmorty217]

Not sure if this will help answer your question but I have 250lbs of live rock in a 220g with a Tomini, Desjaradini, maculiceps,orange shoulder, foxface, and a Quoyi parrotfish.... All of which are grazers, with that said all of my fish are fine together but I feed more than most and feed nori several times a day. I will be rehoming a fish or two to make room for the orange shoulder to grow

 

[fermentedhiker]

It doesn't help....... But thanks for the response. That sounds like a beautiful tank. I wish I had room for one that size :/ maybe someday.

I think tangs are probably the exception since they don't hold territories but instead are roaming browsers. Any rule of thumb is bound to be provisional at best because of individual differences in the species in question. For instance Tangs don't defend a territory whereas damsels are extremely defensive regardless of how abundant their niche food is.

I'm more trying to gauge how people(like snorvich) determine when it is inappropriate to add another grazer strictly because it is another grazer and not because of other considerations.