Hi Terra,
Seahorses can actually adapt to most any light. Mine had been under T5s for years and were fine.
A 60 cube is a great tank for them. My biggest caution would be don't over stock and be diligent about WCs and husbandry. Treating sick ponies is not fun. I just finished having 2 of mine in treatment and it is rigorous.
Be fanatical about not letting seahorses poop or excess food collect any where as that fuels bad bacteria. Also an over sized skimmer (2X- 3Xs recommended with 3Xs being better) can help a lot. I like my SCA-302. For the price it does a good job for a tank your size.
Finally watch the temperature. Keep it under 75°F. Good luck with your seahorses. Where are you getting them? Seahorses Source has high health seahorses at a good price and nobody gives better customer service.