New rock

Will adding more LR to a system cause another cycle?

 

it depends on the amount and LR you add and the size of your system.

 

well it's not mine, but its a 55gal that only had approx. 30lbs in it. no fish. they added another 40lbs (started thinking about fish). they were going to wait anyway, but i was curious for my own knowledge if it would cycle again.

 

That might depend on how big the die off is from the rock. If you leave the rock out of a system or expose it to extreme conditions, it might increase the die off which might increase your chances of another cycle.

Just a guess, though.

 

It depends on if the LR is cured or not.

 

If the rock is fully cured and not left out of water for too long you should not see too much of a cycle.

The smell test always works well for me, not fully cured rock will have a much more pungent ocean smell to it. Not fully cured may have algae on it, numerous sponges and small inverts. All great things to have but you can expect some die off.

When I go to buy fully cured rock, I look for rock that has basically nothing on it but coralline.

 

I would assume that you/they will see some cycle given the proportion of rock that is being added to the amount that is already present.

As others stated, if the rock is fully cured and not out of water for long, you could be okay. I would err on the side of caution.