Tekkit is more demanding than normal MInecraft, but this shouldn't be happening unless you have a massive operation going on. Can you make sure that your temple is set to allow people to walk through it (if you don't mind people doing so) so that someone else can see if there is any lag?
Clearing the cache shouldn't make lag get worse. At this point, I want to see if the problem is on my end or your end. If a few other people don't have any problems at your temple, then the problem is likely on your end, unfortunately.
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Everything is overrated - <D
I would gladly take 90 whippings and be sentenced to 2 years in jail than have my account warned. - NotYou