Should I put light on my live rock?

[Gundy]

I have purchased live rock from my LFS and have put it in my new tank with sand. I’m sure the rock varies in time from weeks to months that it has been submerged in water at the store. The tank has no filtration yet but just a powerhead for water movement. I will be setting up my tank soon but wanted to get started on seeding the rock with bacteria and start to culture some coralline algae. I will be hooking my sump to the tank in about 6 weeks.

Should I put my lights over the rock or is it better to keep the tank with only natural light? Thanks.

 

[tbrown]

Light doesn't do much for rock, just corals. The bacteria isn't light dependent, it just requires an ammonia source.

 

[WhatCouldGoWrong71]

Since you said LFS, I assume we aren’t talking about premium gulf rock that has microfauna and the alike on it. I assume you mean rock that allegedly has nitrifying bacteria on it. If that’s the case, I agree, just a food source (ammonia).

 

[Gundy]

Since you said LFS, I assume we aren’t talking about premium gulf rock that has microfauna and the alike on it. I assume you mean rock that allegedly has nitrifying bacteria on it. If that’s the case, I agree, just a food source (ammonia).

I do want to add some premium rock from Florida to really seed the other rock. Should I wait until my sump is hooked up?

 

[phillyb614]

IMO, do NOT turn on your lights! Almost all the “bad pests” that can take over your tank are photosynthetic. I would not turn on your lights until you get coral. I suggest getting just a couple fish (after the tank cycles) and not even turning the lights on after getting your first few fish. Allow your tank to grow beneficial bacteria and beneficial coralline algae (coralline you will need to introduce to the tank and also doesn’t require much light) to grow in the tank before other bad photosynthetic pests are given a chance to out compete it by turning your lights on.

 

[tbrown]

I do want to add some premium rock from Florida to really seed the other rock. Should I wait until my sump is hooked up?

You don't have to. I usually get the tank up and running for a week or so before I get the sump hooked up and running.

 

[tbrown]

IMO, do NOT turn on your lights! Almost all the “bad pests” that can take over your tank are photosynthetic. I would not turn on your lights until you get coral. I suggest getting just a couple fish (after the tank cycles) and not even turning the lights on after getting your first few fish. Allow your tank to grow beneficial bacteria and beneficial coralline algae (coralline you will need to introduce to the tank and also doesn’t require much light) to grow in the tank before other bad photosynthetic pests are given a chance to out compete it by turning your lights on.

There is definitely some truth to this. Bad algae tends to grow better with lights and nutrients than without one or the other. Bacteria requires an ammonia source but no light. Coralline isn't photosynthetic and will outcompete other algaes if given the time to get a foothold and is provided the correct parameters.