Habitat - Indoor :: Bulb wattage question.

[jdub1107]

Hi, new to the board and also a new res owner.

I have 1-2inch res right now in a 20 gallon tank. I'm planning to get 1 or 2 more res and move to a larger tank, probably around 80 gallons. I'll have to get a multi-purpose light (UVB/Heat/UVA) because I have an aquarium, which has the semi-covered opening that I'll have aim the beam through. I don't want to buy a 100watt light now and then have to upgrade to a larger one within a week when I move the turtle. So I was wondering what wattage I should get and how large the coverage area would be? Thanks.

[marisa]

The multi-purpose light is the combination mercury vapor bulb and this will be used when you get your 80-gallon tank?

For the 20-gallon, you're going to need both a UVB light and basking light. (The mercury vapor light is to strong for a semi-hooded 20-gallon tank.) The basking area should be in the range of 88-90F. Use whatever wattage will get the temp in this range. Don't guess--check the temp with a thermometer.

[jdub1107]

So that would mean that there would be the possibility of having to buy different bulbs if the one I get is too weak/strong? There isn't a general rule of thumb or something that I can go by?

Also, my gf's father said we could use his 80 gallon tank. The only thing is that it was originally made for fish. It looks like two 40 gallon tanks with 2 cylindrical tubes measuring 5.5 inches diameter each, connecting the two tanks together. Would this be a good idea to use? We have 3 turtles now between 1.5-2 inches. I mean, it looks cool, but I'm wondering if I should use the free tank or buy another one?

[marisa]

There's a general rule of 3-5 watts per gallon of water for water heaters, but no fast rule for basking light wattages that I know of. You want to use whatever will get the basking temp around that range. Your turt will tell you what he likes (after he's adjust to his new home if you've got a new one)--sometimes a turt will like it a little warmer or cooler than you have the temp.

You have to experiment a little. If it's too cool, either use a stronger wattage bulb or move the basking area closer to the bulb you have or move the bulb closer to the basking area (but not so close your turtle could burn himself). Too warm, use a lower wattage or move the basking area or light further away. But check with a thermometer to be sure of the temp.

[jdub1107]

Thank you for your help Marisa.
How will I know if my turtles like the temp. I'm thinking of having a two level rock formation (like a step), so they can choose how close they want to be to the light. Would this be a good idea?

[marisa]

You're welcome. Any basking area should be easy to get on, should be big enough for the turtles to comfortably bask at the same if they choose to do so (they may stack on each other) and should allow them to fully dry off (even the underside) when they bask. I don't know if your turtles need two levels to be able to decide where they want to bask, but a step formation would make it easier for them to get on the basking area if they don't have any kind of incline to get on it.

If you're getting new turtles, it can take them a while to adjust to a new environment, and they may not want to bask at first (or bask only when you're not there). But once they become adjusted, and if the temp of the basking area is warm enough (but not too warm) they'll bask and you'll know (you may catch them at it and they'll jump in the water at first). As an incentive for them to bask, you want to have the water temp around 10 degrees cooler so they'll want to bask for the warmth.

[jdub1107]

Didn't want to create too many thread...I read that they may need shade as well? It is true? Does that mean I should have another land/rock area other than the basking zone?

[marisa]

When you mean shade, do you mean when they're outside? If that case, yes, they should have some shade to go to in case it gets too hot for them in the sun.

I don't think they need special shade in a tank. Having a hiding area they could go to for privacy is nice, though, as is having objects like fake plants they can hide under and/or rest on.